the novel I'm looking for is a Bl Qt novel. I remember one of the arcs was a apocalypse arc where the ml followed the mc like a ghost. The mc was a scientist and was looking for a cure(?) he used the ml as his Expiriment(?) or used his blood or something I can't remember. The ml went into coma and turned into a ghost and followed the mc. At first he hated the mc for Expirimenting on him. But a after following the mc for years he fell inlove with him. Then one day he went back to the past when he was treating the mc badly because I think one of his allies were also reborn and he had a crush on the ml. So he told the ml what happened in the past and the ml believed him and so he treated the mc badly. When the future ml travels back to the past he regretted what he did and treated the mc well. Stuff happened and this arc ended with a BE where the mc and ml both died by jumping off a roof(?). I don't remember how they died I just remember they died.
yep definitely FOD ml ddnt die immediately only mc did, ml died when he self-destructed to protect the world and stop the final apocalypse for mc's sake