Where have I seen this concept before..? Lol
I don't care about money as much as I care about sharing my franchise with the whole world but... well I guess if I were rich I'd buy myself a very nice house (not necessarily a big one) and I'd also probably start collecting old videogames, comics, books, etc. 
First, I'd spend some time writing letters. I'd put the letters in a safe deposit box in San Francisco, then taking the time to settle on a farm in the Midwest.
After getting married and having kids, I'd start telling them stories about the letters, but I would stop telling them the stories once they became teenagers. Once I'm old and on my death bed, surrounded by my descendants, I'd tell them that hidden within my novels are the secret to finding the letters, along with the key to my fortune.
I'd make sure to leak the existence of the letters and my impending death to the media, causing my book sales to skyrocket and for the value of my estate to increase in value as well.
Then I'd die with a smile knowing that within those letters are nothing more than the words, "Now people will remember me."
Give me like a hundred thousand bucks, and after debt and moving, I'd put half into investment, and the other half right back into the Quinlan Circle, which is in desperate need of good website design, artwork, and an actual social media presence. And I'd pay a year's salary to myself and just go ham on writing, like a book every month or something, just to beef up the Quinlan Circle's library bigtime.
I've lived for a few months writing full-time before, in between jobs. I was actually making a plan of how to make a living from that when I got accepted into the JET Program unexpectedly and moved to Japan. But in those months, I really did write tens of thousands of words a week across several projects. It was sort of wonderful, but I didn't have any income or savings to support myself, so it wasn't going to last much longer if I didn't run into a windfall. If I ever get that chance again, I'd really like to take it. $100,000 sure sounds like the right number to do that for me.
Wow, the world really would be a mess if the crap I created got super popular.
I would pay off all my bills, get a medical and mental health check-up, then put the rest in savings. Every month or so I would donate some to charities I like, and leave 200% tips to really good waiters/waitresses. If I was really well off I may sell my current place after fixing it up, then move out of the US to some place more quiet. Like the woods or a field with no neighbors somewhere in Europe. Help fund indie projects, buy stuff at artist alleys, maybe even go back to school and not worry about being hundreds of thousands of dollars in debt.
I say all this but in reality I would probably just give it all to my mom, we live together because I can't afford to be out on my own, and she has a lot of health issues. So her happiness is my happiness, if you know what I'm saying.
I'm a huge dork. Since this is a fantasy the first thing I thought of was "complete my manga collection with all the volumes I'm missing from series I only partially own".
We're daydreaming right? After doing all the practical stuff, helping my family and subscribing to all the Patreons I wish I could support, I'd spend a crapton of money on a ridiculous mansion with an enormous library and beautiful office for me to work in. My closet will be full of pajamas so fancy no one can tell if they're not just really eccentric clothes. Of course I'd need my house staffed like maybe with a personal assistant, cleaner, gardener, personal chef... Maybe a trainer? My cats can eat salmon and steak every day. I'll take a theater, ice skating rink, and pool on the grounds of my estate. Maybe a squash court too, why not? And throw parties (I'm thinking masked balls) and host board gaming events if I'm feeling social. 
Rich author = famous author (this can also applies to anonymous authors out there!)Have a lifetime guarantee of ensuring you and your own family's maximum security to prevent any unhealthy disruptions towards personal life. This includes I.P. theft, plagiarism, rogue hackers, terrorists, thieves, unwanted paparazzis, and insignificant others. For fans and enthusiasts, please line up and communicate in an orderly fashion. The renowned best-selling author remains open to any questions.
Security should not be a hindrance towards you and your fans but is a way of taking care of each other from the possible threats against well-built relationships.
Chickens.
I always wanted to raise chickens in my backyard because they're awesome.
That mostly means I would be able to afford a small house in the countryside and grow vegetables as well.
Wait, I realize I'd go Stardew Valley all the way.
After all the practical stuffs (loans, family, job security, IPs, series continuation & adaptations, charity etc.), I'll build a spaceship, load all my favorite things on it and never come back.
Pretty sure being a rich author isn't even enough to cover expenses for all the practical stuffs, though.
First of all I'd deal with current finacial issues, like my student loans and the student loans of my siblings.
Then I'd...
- Buy a house. Something not too small, not too big but with a lovely yard. Hopefully somewhere near a forest or a lake, where it would be calm and peaceful.
- Buy the Ball Chair by Eero Aarnio1. I just really want that chair. This is my extravagant dream I actually plan to achieve one day.
- I'd start a retirement home for old homeless cats. It would be a safe place where unadopted cats could grow old in a warm and comfortable environment.
- I'd order a whole bunch of commissions from artists and give them all ridiculous tips.
- Of course, charities would be important. Besides them I'd also like to invest in things that could bring something good to the world, such as renewable energy sources.
In general I would just try to be generous with the wealth because sharing is caring.
build a house with a lot of secret passages so If my wife has people over and I don't wanna say hi but I want a snack I can just use the secret pasaage to the kitchen. Also have a pool that connects to a hot tub in my bedroom trough an underwater tunel...though there's a posibility that I might get trapped in the tunnel and drown
Maybe take a trip to Disney World and stay at the Polynesian resort. I would also like to visit the Northern Marianas. I would also like to take an animation class, one that actually teaches animation (unlike the ones at the college I attended). I would also give some money to my family.
Other than that, there isn’t really anything too fancy that appeals to me. I find a lot of super expensive things to be gaudy, ugly, and pointless. I do think mansions look cool but practically I would probably hate living in one.
i would pay my boyfriend's debt; he asked for it to open our clothing brand where I design, so I think this would be the best idea. Also independizing from my parents; this is hell here (and not a beautiful hell like the one I draw), I would like to have a beautiful wide flat all decorated on my own likes. I would also do a clothing collection based on my demons (with leather clothes, which are expensive!), and to invest in things related to my comic and fashion brand.
Of course I would also do some things to help others; subscrive to a lot of patreons (I'm only in one now), buy my friends' brands' clothes (and to other alternative indie brands), maybe some charity too, helping cats and other animals... etc
Now comes the extravagant part, If I was like REALLY rich I would build some of my demon princes' palaces 
and maybe make them work as hotels or residencies, or just a place to visit for the fans with some exhibitions and stuff, idk, but always in a good place and respecting the enviroment.
But first of all without a doubt paying my boyfriends' debt and running away from my actual home
I have a lot of ideas and needs so just give me the money, we are poor and need it 
(As I cry, I will make some promo, I hope you don't mind)
