The Complicated Diary of a Stepbrother 大江戸ウメコ

My parent had remarried, and I got a new older sister.
My older sister who I thought as annoying had become my family, and then, before I knew it, my feelings for my older sister changed into love.
*This is the stepbrother’s POV for the series Lean Tuna and Her Stepbrother’s Plan to Become a Fatty Tuna.