No ! The friend he gave hints about liking him is Yeo Eun Ho
You can go back and watch the scene where Yeo Eun Ho asks Kwon I Hyeon for advice about liking a close friend. The story that he tells forms the basis of the spinoff set to air later this year.
It's the spin-off Dongjeolgi with new classmate Kwon I Hyeon as the lead. It's based on what happened at his old school but set years after they graduate and fate brings him and his friend back together. From the synopsis it sounds way more toxic. Whereas Summertime has a lot of warmth the spinoff sounds very cold at least initially. https://mydramalist.com/804376-dongjeolgi
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https://mydramalist.com/804376-dongjeolgi