I have thought about this a lot lately. I am nearly enraged when I am reading a comic that uses nudity to arouse the viewer a bit but they don't draw the women with nipples. Right now in anime/manga they draw a ton of risque artwork that doesn't quite cross over into R material because the nipples are magically hidden, or just not there. I think it's pretty tacky.
But I think it's weird if I see nipples on male characters, ahaha. I guess it's like how I don't want to see armpit hair or chest hair... I'm not a male nipple fan so if they are excluded, it's all good. But in my series I will have bare-chested men and I often draw them nipple-less but women's nipples I will draw, and I've wondered if this is weird.
With women, boobs are like a beacon leading your eye to find the nipple, or like a target with bullseyes. They even jut out ready to poke you in the face. But in real life, a man's nipples may be really tiny or hidden behind matted hair, so you don't really notice them as much as a woman's.
I've kind of decided in my comic FaLLEN I will draw the men nippleless unless there is a close-up, in which case I will draw some indication of nipples (probably Triton nipples) or nubs. My comic has tons of girl nipples, so I really shouldn't play favorites here.
@zelkats Little boy nips weird me out too! Little girl nips are world-endinglly awful, though. I doubt I will ever draw little kids with nipples.