Obviously Fjord? I don't think I can imagine anyone else being the ML... Still is obviously Bro zoned and there is no other guy her age around her with as much connection as Fjord!
As for his death based on the past life, I think the author will change it in this timeliness...
He was either killed because he didn't act according to the wishes of his mother in the past life and rebelled by being a womaniser and drunkard, or he committed suicide because he felt that much hopeless against his family and wanted to push back their plans by exiting that way....But now he met Lyrica and wants to impress her and her to like him, so he is on his best behavior, a knight in shining armor. Still rebelling against his mom but he doesn't destroy their image of "noble beings" so ig they are keeping him alive. I would bet they will try to kill him off tho when they realise he is an obstacle to their plans and sit his "sister" in his place
I think the implication is that he killed himself because he found out about his "siblings". I think what we see in the story is an alternate branch where Lyrica tells him "don't break, don't fall apart" and because of that he's able to move past feeling like he's not a real human and chooses to kill the other experiments to free them rather than giving into the horror and killing himself.
His mother chose to show him this because "he's in a rebellious phase", to break him. In the previous timeline, we know he did all that stuff to rebel as well, so she would've broken him then and then he would've "died".
Whos the ml here? Lyrica will end up withhg???