Maybe he was testing him? Like he wanted to see how much the MC loved him because he wasn't sure if the MC really loved him which is again messed up that he was testing him BY PRETENDING TO BE DYING FROM POISON but since he wasn't really taught how to properly show his love and to talk about how he felt, he thought this could be a way to see.
I would throw ice cubes at him with you if I could (〜 ̄△ ̄)〜
I think the reason why Jinhwa is so.ruthless in his past live is because he doesnt know how fragule human really is. No one made him realize the 3 important things that yeondam just said to him and thinks that jin and human are partially the same. He break his ankle in his past live because he didnt want yeondam to leave him but didnt know that in the process it breaks yeondams heart
In raws seme even had another man he often slept with though…he wasn’t a human like uke was, he had red hair. When uke meets reincarnation of the man seme was also sleeping with, he says (according to the transalation) that he was a hobby of seme and so was uke (he doesn’t know seme loves uke now tho) sooooo it looks like the mistress guy had feelings for seme as well
Heres my utmost earnest opinion
so like:
In his previous life where Jin Hwa was a complete asshole I think, mabey he actually did love the mc but didnt potrait it right or wasnt taught much how to care for his loved ones so he did it in a way he thought would show his affection ,though, he was selfish a lot so it would be understandable for the mc to fear or even dispise him... but I still dont understand y he would uhm like trick the mc to thinking he was poisoned that really got me wanting to throw an icecube at him mabey that heal his jerk like smug face