I mean Lukas was just a kid too. He and FL were so close, obviously he was hurt and scared after FL started avoiding him after he got his powers. Even if it was for another reason, he didn't know that and misunderstood that FL thinks of him as a monster. The two used to be so sticky before FL got her past life memories that it's not surprising how clingy Lukas is. Before it used to be mutual clinginess which is why it seemed normal and cute, but since FL has other things she wants to do now, it looks like Lukas is way more clingy.
Also, I don't see why FL needs to distance herself from Lukas. Tbh the only thing Lukas did bad in the future was fall for someone else and forget about FL who was waiting for a reply for her confession from Lukas. There's really no need to stay away for Lukas, FL just needs to make sure she doesn't fall in love with him and everything will go fine. She won't be heartbroken or anything in the future. Unlike in other stories, FL doesn't die because of Lukas, the hero.
Childhood friend's level of clinginess is turning me off from this story SO BAD. And it might be a translation issue or just how it's narrated, but I'm not a fan of MC's wishy washy attitude when it comes to Luka. I'm so confused. What exactly was the plan??? I thought she needed to distance herself from him but...???? ರ_ರ Nah, she just let's him do what he wants. What a headache.