Premieres January 11, 2025. The new PV is here. Check out the Crunchyroll article for more info. Synopsis from AniList:
When Sakamoto meets Aoi, the convenience store clerk, it’s love at first sight — and just like that, he retires.
Sakamoto gets married, has a daughter, opens a mom-and-pop store in a quiet town, and completely transforms … into a plus-size man. To ensure a peaceful life with his beloved family, the legendary ex–hit man bands together with comrades to face off against the looming threat of assassins.
I think the easiest comparison is probably spy family, or comfy but with a wacky core topic. In Spy Families case that's the whole Spy dad and Assassin mom. For Sakamoto it's assassin's lots and lots of assassin's