"trap" is a slur. It's been called out in anger prior to assault and even murder. I even vaguely remember hearing at least on police tape on TV of an assault where the words was being screamed by the attacker at the top of their lungs.
If you didn't know before, you hopefully know now. If it was ever fun, playful or innocent (i.e. when anime cons had contests and such) it hasn't been for a long time. When you use "trap" in a space with trans people, they don't immediately "get offended" like you might think. Their blood runs cold and they begin to feel fear. Like swallowing a knife that had been in the freezer. From there it's either fight (calling it out) or flight (keeping their head down). But that moment of pure cold fear is there, every single time.
If you're a good person at your core, please don't put other people through that. I'm not going to make demands or saber rattle. I believe most of you are good people and can understand.
Anyways, this chapter is super cute and I was very much looking forward to it.