@Eksentrysyti she's not disinterested in him, more like she's put off by the eccentric things he bought which are most likely scams directed housewives making it way funnier. Her role is the "straight man" of the jokes If not, the jokes involving her would not be so entertaining. Tatsu is an ex-yakuza who became a housewife but does everything like a yakuza in a town of many yakuzas and ex-yakuzas doing things yakuzas don't typically do, I would not adapt to this if I were given 100 years. There has to be love between them I would like some backstory on how these two met, my guess is that it will be a mundane situation but that's just me.
@Tumbling I don't think the grin joke is old per se I just think it felt flat this time since we aren't given what Tatsu thinks when he does that. I felt that some input from him like "This actually feels great!" or something would greatly enhance the joke or maybe we should be guessing the punchline ourselves.