
to be honest i don't think the author made a big emphasis about jaewon (mc) and junseo's relationship as something platonic, which is sad because platonic relationships doesn't have a big relevance... and here's a lil spoiler:
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junseo starts to get romantic feelings for jaewon, so yeah, not platonic

Leaving my personal preferences aside, I think that it would be more reasonable Jaewon stay with Junseo. They friendship its cool and all, but they would make a great couple. They can help each other with the scars from past and build a great relationship. Idk, for me it seems right they end up together.
or does it seem pretty obvious who the MC is gonna end up with?? bc it doesn't seem like a harem manhwa at all - if you look at the four other male characters on the cover page, it's the orange haired guy (who is clearly friend-zoned af & doesn't seem to have feelings at all for the MC), junseo (who also seems incredibly platonic w MC) and then red haired guy & garam who MC is literally obsessed with. like ofc he's gonna end up with Ga ram