I think this was a transmigration/world hopping novel. Same ML for all worlds but when going to a new world the ML there doesn’t remember the previous world until later on around 3-5 worlds maybe. In one of the worlds the ogFL’s dad adopted ML from an orphanage bc ogFL saw him and liked him (his looks i think). When they grow up ML thought the dad adopted him to marry his daughter so he schemes himself out of this but this was just a misunderstanding although by then years later it was too late. ogFL marries this other guy bc of ML (part of his scheme and I think it was bc ogFL wanted to help with business(?) or bc when she asked what he thought about that guy ML said he was good). I think ML’s scheme was also bankrupting the dad’s company(?). Anyways, after ogFL marries Ml leaves abroad and everything goes to shit with ogFL. Dad get’s sick(?) and dies, her husband is trash(?), and I think ofFL also dies(?). When ML returns later, he’s shocked to find out everything that happened and didn’t expect things to turn out that way. Transmigrated FL thinks about ogFL and feels sorry for her about how she actually loved ML but bc ML said the other guy was good or whatever she decides to go after him instead. This is the only world I remember and I think it was the first world. Idk if I remembered correctly tho. Also, transmigrated FL takes her mission seriously like every world is a bad ending and ML suffers but this is only in the beginning and gets happier later on I think when ML starts to recall the previous world or has a vague sense of his other memories/world and tries not to mess things up.
Transmigrated Canon Fodder, Please Calm Down! I think? The arc description mostly fits the second arc but I don't know if the ML remembers the previous worlds later on.