It was a brother/sister wincest with the sister returning from studying abroad for a short while. Her brother ignores her coming home because of his feelings for her. Further in she reveals she loves him the same way because he is her "sun" (His name also means sun? Hence the saying) At the end she has a new necklace in the shape of a sun and says she got it from her lover. Been looking for days but no luck, Some help would be appreciated! Edit: It may be part of a series now since the writer and drawer both had multiple stories with the same genre back when I first read it. Edit 2: Found it on a random hentai site, it's called "Subaru's Sun" Can I get someone to upload this to Pururin? I'm not fond of that sites layout, Please and Thanks!