not defending it, but i find people are way less forgiving about it when its gl or bl
seen people respond to forced kisses in straight manga and webcomics with disgust (unless it's the romantic lead in which case they just squee) but they only ever call it SA when it's gay
I think the big difference here is that she's asleep. If someone forces a kiss and the other party can technically shove them away, that's not as awful. (Also, she could have gone for the cheek and not lips, etc.) But because she's incapacitated, it could be seen as assault.
That said, I don't think SA is necessarily the right term here? That might be a better one to keep for a more aggressive approach. Regardless, this is the kind of behavior that's uncomfortable in manga (as in RL) regardless of orientation. I think calling it out is a more recent development among readers, and I can't say I'm upset about that trend.
If you really love someone, you can also respect that they may not reciprocate your feelings, and you don't have to try to force your emotions on them. (It can be more challenging as a teenager, because everything feels really intense when you're going through it for the first time, but it's a good lesson to learn.) There's a big contrast between the two 'relationships' we see here ...
Edit: I used a lot of words but the point I was trying to make is that queer or straight you should not kiss people when they're unconscious! In fiction it can be seen as romantic, especially if the other party actually secretly likes you back. I'm only giving her the benefit of the doubt this chapter because we have yet to see the response. But it is also clearly not cool to kiss people who aren't into it. Or people who are already in relationships. 🙄