Remember that in the last chapter she literally tied her up?
As she proceed to first just wipe her. And that's hardly just BDSM.
intercourse without given consent, a.k.a: rape
Intercourse ? Didn't she just suck her nipple one time ? And she barely smooch her breast here. Does that really count as intercourse ? Sexual assault yes but not rape.
I mean... you're technically right, but like, does it matter? They're both deplorable actions. And Hayami probably would've escalated it to rape if Akane hadn't freed herself anyway--at least she says she wanted to.
I'm not sure this distinction matters much outside of a courtroom.
Words, both inside and outside courtrooms, have defined meanings. Granted, the meaning of words can change over time, but we should respect the current meaning of a word and use it in the proper context. This is important if one wants to convey their thoughts to another and not be misunderstood.
For example: My understanding of chapter 3 is that Hayami physically restrained Akane, and committed sexual assault with intent to rape.