how?
He agreed tho?
it’s indeed pretty rapey. he didn’t really consent with a third party joining/observing because the top pretty much manipulated him into a really bad sm relationship. it’s not really rape but still, it’s enough of a dumbass behavior ╮(￣▽￣)╭
The uke never consented to being watched by a third party. Imagine this: Your lover proposes sex with a blindfold, you agree because you trust them enough to do so. Then in the middle of sex, you hear a voice, an unfamiliar voice complimenting you and saying they want to screw you (since you're just their type). It's the voice of a gender you feel no attraction to (whatever that may be).
Some people may be okay with this but the uke was not. He was scared but didn't want to let the seme down. He knew that if he denied the seme then he would not be happy/satisfied. Basically, he felt pressured to consent to the third party. Even though he is 1) not interested in women and 2) didn't feel comfortable with anyone else there.
Spoiler:
A situation similar to this happens in the future and the uke hard rejects it (pissing the seme off). By then the other love interest has already come into the picture and his feelings for the seme have faded which is why he doesn't care to listen to him anymore—denying sex with the two men he was being forced to have sex with while the seme watches. Plus, instead of comforting the uke who was scared and crying, the seme treats him very very harshly.
That’s rape but okay