Boris Akunin. Pelagia and the white bulldog (№ 151198)

A man is like to one, female zero. When you live each by itself, it cost little, she does no, but should they marry, and there is a new number. If the wife is good, she is getting the unit and its power increases tenfold. If bad, then climbs ahead and the same time the man weakens, turning to zero point one tenth.