MIAE-106 Every morning, my little brother is treated like a pet and caressed, but my tsundere sister Mari Rika doesn't give a damn about me

My brother is annoying and disgusting, I have no interest in him at all... but his morning wood is so cute that I fell in love with it!? The sister who decided to keep the morning wood as a pet comes every morning to nuzzle it, suck on the glans, or even use her vagina as a house and insert it! My brother is just an obstacle, so I act coldly towards him, but his morning wood is so adorable that I can't help but melt! The complex triangular relationship between brother, sister, and morning wood incest!