>>281770423
That's Kiriko's mom, and sort of a motherly figure to him, even before her son married Seina's little sister.
But before he got shanghai'd into the GP, the plan was that after both her kids had their family secret revealed and went into space, Seina would get handed off to her, more or less as her new husband.
And even after he married her daughter, she was still eager to claim her right.