She's Adopted a High School Boy! Vol. 12 (Kodansha, 2022)

""If you're happy, I'm happy"" is the motto of the next-door neighbor who paid off Minoru Soramoto's family debt and took him in, all at no charge... Where will this exciting new life with the mysterious lady lead next?! Minoru and Shiori-san have finally made it official, and are trying their hand at different couple activities (Minoru is especially keen) when all of a sudden, out of nowhere, Shiori-san's profession is finally revealed! And not only that… but Minoru discovers an even bigger secret and their relationship reaches its hottest point yet!