Can you want to have lesbian sex but not be lesbian or bisexual?

Human sexuality is very complicated, and homosexual desires are normal and natural. If you do not wish to identify as LGBTQ despite having these feelings, that is also valid. However, generally, having sexual attraction to the same gender would qualify you as lesbian as bisexual by definition.

Experiencing sexual attraction towards the same gender is only possible for people who are either homosexual or part of the bisexual spectrum. However, it is possible to have a strong preference for men bit still have some attraction to women, which would still be considered as bisexual since the attraction doesn't necessarily need to be 50%-50%.

Of course. How you identify yourself can be different that what you "do". For instance, you can identify as a heterosexual woman and be in a relationship with a girl (the exception that confirms the rule, if you want ^^). Your couple will a a lesbian couple (because you're two girls). But that doesn't affect your own way of identify yourself. If you want to label yourself as bi, then go for it. But if you don't, that's ok too. The distinction between the relationship label and your own is important because by labelling your relationship, you're not the only one concerned. Your partner is too. But the way you identify belongs to you and only you. Just keep in mind that if you happen to be in a relationship with a trans person, the way you identify can sometimes be heard like a denying of their own gender. It's important to assure them, in this case, that labelling yourself doesn't change the way you see them and their gender. :) If you're in a relationship with a trans woman, you won't have straight sex, it will be lesbian sex, since you and her would be women. Your couple would be a lesbian one. But you could still identify yourself as straight, in a relationship with a girl. Keep in mind labels and orientations aren't fixed, they can evolve, change by themselve etc. So let's stay open about it :) And maybe just check if not wanting to label yourself as bi or lesbian isn't due to misconceptions, stigmatisation and some interiorized homophobia, but just to the fact it's not what fits ^^