I do think it's biological, it makes the most sense to me. I'm not sure the environment can play such a big role when it's something present among all/most mammals. Sex is instinctive, basic, something we're kind of hard-wired to do like breast feeding or peeing. But that's just me.
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About the boyfriend thing:
- Close to my age, I don't mind a bit older or younger, just no huge gaps.
- Best possible scenario: he doesn't drink. I'm perfectly okay if he does, though, just not a ton. I don't like when people can't have fun without alcohol.
- He doesn't smoke or does it when I'm not around. If he does he tries to not stink 24/7.
- Calm, I can't really see myself with someone who gets angry easily.
- Funny. If we're not laughing a lot then I lose a bit of interest.
- Tolerant. Live and let live, I don't like people who develop very strong opinions about personal choices of other people.
- Not too needy. I'm an individual, not your "other half"

I enjoy privacy and individuality.
- I actually don't care about former relationships or children - but since I'm 25 I'd imagine I won't encounter a lot of divorced guys with children

- Likes animals, science-ish stuff, history. We can watch documentaries together

- Being into gaming? That'd be too perfect, I don't think I'm getting that to be honest :/
Looks:
I don't really have one particular "ideal" look since I like a lot of different attributes that often clash with each other. These are bonus points, though:
- Overall thin, but toned. Abs FTW.
- Dark hair.
- Glasses.
- Casual clothing. Jeans, jackets, t-shirts, etc. - Not that I wouldn't date a more fashion-ish guy, but I find someone who isn't in love with fabric way more relatable.
- I really don't care about height, but the closer to mine (1.78cm) the better.