For future references, you don't have to post the same thread to multiple sections XD
Sometimes, you can just call @STAFF, and one of the mods can help as much as they can.
As for your question -- I believe you can send out an email and converse about this series idea. Of course, you would have to have everything ready to go -- story-line, the beginnings of developed scripts, characters with prototype designs. It would be good to have an idea developed and your reasons as to why Tapas should pick you up. Sell yourself and show yourself -- don't just be like "I have this great idea".
It's also about hard work as well. You can contact Tapas, but you also have to make them care. They have to see previous work you've done. Do you have a portfolio? Do you have comics you've previously posted on other places? Do you regularly promote your work and the work of others?
There can be a lot to think about when you want to become an Exclusive comic. But again, maybe someone from STAFF or a veteran Tapas creator can better answer this for you 
