The "bad guy" / guilty party's PoV

This is one of those golden cases where we have a total mix PoV.
I personally love this manhwa a lot.

For the thoughts of the bad guys, you'll have a sadistc sociopathic serial killer, an obsessed & hallucinating girl, rapists, racists, homophobic parents, dirty cops, and how jealousy, envy, suffering, fear, traumas, can twist people. And they all have their own circumstances - that forced/ shaped as they are today.

Oneshot ch.1
MC: Obsessed, Sadistic disorder. Seme

A photographer turned a poor abused boy into a model in his own weird way of taste and even treasured those photos more than the real one.

Story ch.5-6
Alt PoV (his PoV is in ch.6)
MC: Isolates the uke, POSSESSIVE, Abuse, bullying, rapes, Obsessive love disorder. Seme (Aki)

Being bullied by and forced into having sex for years w/ his childhood friend, forbidden to talk to anyone else, Keito always thought he was hated by Aki, though he didn't think it through; this isn't hate, but Aki's attempts to monopolize him.

MC: Rape, blackmail, confinement, abuse. Seme (Saeki)

A salaryman who always fails. A guy appears when he wanted to give up and gives him glasses that will change its wearer into a dominant brute...

Pairing: Tykki x Allen
MC: Pedophile, Yandere, Two-faced, Orchestrated dependency (fear-focused & by isolation). Seme (Tykki)

Alt universe. Tykki finds a child Allen & decides he wants Allen all to himself and will stop at nothing to isolate the boy so that he only sees him.

ch.2: https://myreadingmanga.info/loveseat-love-is-blind-2-d-gray-man-dj-eng/
Tykki and Allen have begun traveling together. Allen lives in fear of the Akuma while Tykki delights in toying with his young companion.

Pairing: Yukio x Rin
MC: Multi-rape, Abuse: the limit & morals to what he does getting more blurry as days repeats themselves w/o him getting found out. Seme (Yukio)

Yukio harbors incestuous feelings for Rin. He tries not to give in to them, and to be content with their current relationship. However, when he learns that time is on his side, he increasingly takes advantage of it.

MC: drugs the uke, SM torture, 'rape'. Seme (Noda)

Noda-san, miserable after his ED-caused divorce, overhears his subordinate, who adores him, mocking his problem, and decides to get revenge by making him feel as miserable as he does... Who'd have thunk Sawatari would react the way he does? ;)

MC: constant sexual harassment. Seme (Honda)

Honda and Shibuya are neighbors & work at the same company. One day Honda discovers Shibuya wears men's lingerie! Shibuya tries to explain his fetish; at first Honda didn't care but got sucked into it & ended up finding himself unable to resist the urge to harass him!
Well, it's a comedy, so don't expect anything heavy, but it's well done: his thoughts sound definitely realistic enough to belong to the list!

Pairing: Erwin x Levi
MC: Obsessed, intercourse w/ sleeping uke, Rape. Seme (Erwin)

Reincarnated Erwin is plagued w/ nightmares about his past death & wishes nothing more than seeing Levi again. Luck brings Levi to work as his secretary, but he doesn't have memories of their shared past. As time passes, Erwin's urges escalate, until the point of no return.
Part 2:
https://myreadingmanga.info/melomelow-hyura-goodbye-second-half-attack-titan-dj-eng/

MC: selfish manipulative exploiter bastard fufu! Uke (Kyunghee)

Uni student Kyunghee just broke his relationship w/ Sihyun, a sugar-daddy whose excessive infatuation & clinginess was just too off-putting. But soon he has to deal w/ a vindictive Sihyun, who started to date his mother, while trying to fool his new victim Kim Junsik, a smitten ex-classmate he plans to take advantage of & use to get revenge...
I'm glad I bought the chapters on Lezhin :)