I, Tono Sawa, have a sister.

My sister has a boyfriend, but it seems she stole him from her childhood friend. And not just that, she apparently framed her childhood friend as the villain to do it.

I don't think such actions are right, but… unbelievably, my sister went to pick out a ring for her ring finger without giving me a single chance to voice my opinion.

However, such a sister's true colors were bound to show.

The happiness she stole didn't last long.