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Intro. An older woman, kind but a little nosy. She has known the protagonist since she was a child and treats him as her own son; he calls her aunt. It is unknown if she is aware of the harassment that her daughter intimidates her. Sea as sea, is the target of his revenge. Due to her husband's absence, she does not have much sexual experience and feels unfulfilled. She is the neighbor of Boku-kun's house when he was young. She works as an English tutor and is also the anonymous mother of Sera Narumiya.

Sera no Haha (Gaki ni modotte Yarinashi!!)

@Killua