I have no idea what's going on anymore and I'm afraid of reading past chapters out of a fear my brain will suffer a stroke trying to decipher what's going on.
Himari is friend, they promise to not catch feelings for each other when young.
they grow up.
Himari likes Mc, but decides to add another girl into the picture??? Pushes Mc to become conscious of both her and another girl at the same time, male friend notices all of this. tries to push the other girl into the spotlight to make himari fess up about her bullshit.
Himari flips out, becomes hoslite and gaslights/manipulates MC so hard that he comes crawling in front of her, ready to literally destroy his future for a girl who treated him like shit because she was upset by the obvious directions her actions were pushing MC into.
I guess there are more details but this is literally all the interpersonal relationships have amounted to here