MC and ML (lovers) reincarnated in modern Korea but only MC remembers, so for now MC's lover is basically ML's second personality. I can already smell the "Do you love me for me or for AU!me??"
ML has a second identity that is the one who initially starts having sex with MC. MC knew it was him since the beginning, but ML doesn't know that and literally gets jealous of MC's relationship with his other identity
The 2 "male leads" are actually just younger!ml and older!ml
In the novel side story, ML loses his memory and starts a relationship with FL as a "new person". Well, both as "ML with no memories" and later as "ML with memories" he gets jealous of FL's relationship with the other version of himself LMAO
ML finds out that MC has a son and a supposed alpha woman who impregnated him, and he's DEVASTATED. Little does he know that the alpha parent of the child is... actually him
One of the MLs (it's poly) becomes jealous of MC's "first love", without knowing that it's himself from MC's past life before regression. Well, being jealous actually makes sense because the story later clarifies that the 2 AU selves became 2 separate individuals (the past ML even shows up and fights the current ML)
ML is TERRIBLY jealous of MC's first love, his savior from his previous life, without knowing that it was actually himself
ML becomes very jealous of MC's "past lover" that he's still in love with. Even after MC reveals that he regressed, and that it was actually ML himself from the future, he's STILL jealous of his other self lol
ML gets jealous when MC talks about his deceased past lover, but it was just himself from the parallel universe that MC is from. He's still jealous even after finding out that it was his other self
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