Okusama wa is the smutty precursor to Okusama ga Seito Kaichou.
Liked the Okusama ga Seito Kaichou anime that recently ended, but wished the author had the main characters actually fuck? Well you’re in luck as the anime and manga were based on a short hentai doujin the author drew four years prior. The title and characters are essentially the same, she just changed the “wa” to a “ga”.
Okusama wa Seito Kaichou manga fanservice compilation (1 Volume)