spoilers-------
based on raws and my limited knowledge of korean, i think he ends up with no one but is still close with his two other friends
this hurts my feelings but thank you kind human
spoiler
Naru not ended up with anyone, this webtoon have open ending, but tbh its more leaded to SjxNaru and Naru himself still close with his friend we can see that too in author instagram, but theres a moment when naru have a tenuous relationship with seungjoon after seungjoon reveal all what he did and confess to him ಥ⌣ಥ, and also seungjoon think "I kept regretting. I wasn't able to be a friend anymore because I told you my heart, but on the other hand, I thought like this. I never thought of you as a friend, so I didn't regret it, i did it from the beginning" huhuhu but gud thing is their relationship got better in the last chapter and in author Instagram there so many Sj Naru moment
im gonna sound like a pathetic helpless loser but who has spoilers of who naru's gonna end up with? so i know if i'll drop or not,, i started reading this manhwa solely for the shounen ai after all im srry