I think I'm gonna keep this one as a drabble!! However, I can tell you what happens next.

Riki of course has temporary amnesia because instead of the surgery getting rid of the feeling to love (like most stories), it got rid of any memory of that person. Of course since it's only temporary it could either be Jake telling Riki everything, taking him places they used to go, or Riki gains his memories back randomly at some point in the future.
Riki has some displeasure around Jake when the memories come back however no Hanahaki. Jungwon and Riki both end up getting together after Jungwon spends more time with Riki during recovery. Jungwon confesses. And yeah, happy ending!!