Sending Thoughts on a Moonlit Night

Romantic feelings for my brother-in-law. Not thinking it will ever be reciprocated, the older brother has kept his feelings hidden and lived as a brother-in-law. After getting a job, the younger brother-in-law suddenly visits the older brother, who had been living separately. This is something like a prototype, wondering if I can write R15 BL. I would be happy if it brings even a little warmth to you.