https://www.dlsite.com/maniax/work/=/product_id/RJ01064962.html
Textless version starts on page 76

这作者画的都是血妈胃疼的剧情，就不能画点皆大欢喜的吗？

Base +5, chacf -6, a18827523880 -6, 吃饱喝足去逃避 +3, ADIN0 -7, aneame -6

Title say everything.
Black hair guy is the girl boyfriend.
Seems that the story starts in some private dojo/gym, the girlfriend just defeated the guy but decided to give him a eyecandy, something happens or right after or ina following session she gets beaten down from the blond guy and raped.
Following the title she can only get pregnant after defeated, some bullcrap about the amazonian blood only accepting a stronger male probably.
After the rape the couple does it still beaten down, so the blond bastard put both down, from the girl expression she disliked it...but not totally, no idea if blondie threatened her with more violence or her body simply bends to the winner.
Anyway after the blondie is done with ehr she fucks her BF, probably trying to overwrite the terrible experience, but she can't feel anything, following that she masturbates and seems shocked to or being unable to feel even that or maybe only being able to after thinking of the bastard.
She somehow meets with him again and this time is fully servile, but he is a bastard and just likes to torment her.
Black hair kid most likely was abandoned when she called blondie.

Base +10