Ah yes, the ugly bastard tag...I'm glad it got added, truly. Helps temper your expectations.
"I have to protect our future happiness"? Well...I think the way to do that would have been to refuse to be blackmailed, and talk out the situation with your boyfriend. I'm sure he'd be more than willing to do something, even if it means losing his job.
Only in Hentai does a blackmail scheme over some kissing enable the blackmailers to leverage her into a multi-creampie DP!!! She's demure, young, and in love but rationalizing that the risk of the one was more dangerous than all the excesses after would make her either delusional or just stupid. Does she have to be stupid? You could have added a page or two where she shows that what bias really been happening is that she had been masturbating in furious frustration after every kissing session with the boyfriend and had had enough of waiting. Let her completely own her choices and assert her desires without the obligatory anchor of feeling guilty about her behavior or moping after the boyfriend! It's almost 2023, she doesn't have to be a victim of anything in order for the sex to work! Just saying...
Hello Minato Itoya, my old friend
I've come to fap to you again
Because a boner softly creeping
Left its seeds while I was reading
And the vision that was planted in my brain
Still remains
Within the sound of silence