Masou Gakuen HxH - MangaDex

Hida Kizuna possesses the HHG (Heart Hybrid Gear) ability, but it is not strong enough to make him particularly important. His older sister calls him to transfer to a strategic defense school, where many of the students (many of which are large-breasted girls) use their HHG abilities to fight invaders from another world while wearing extremely skimpy pilot outfits. Kizuna's fighting ability doesn't measure up, but his sister has another plan– apparently having erotic experiences with Kizuna will allow the girls to replenish their energy or power-up. It looks like his new school life is going to

Shin Mahouka Koukou no Rettousei: Cygnus no Otome-tachi

Masou Gakuen HxH:Volume 4 - Baka-Tsuki

Masou Gakuen HxH - MangaDex

Hida Kizuna, Hybrid x Heart Magias Academy Ataraxia Wiki

Hida Reiri, Hybrid x Heart Magias Academy Ataraxia Wiki

Read Lazy Dungeon Master 5 - Oni Scan

Maou Gakuen no Hangyakusha - MangaDex

Source: TB is sulking again enty! Me:Let her loose TB use Outrage! - - Ship Waifu's KanColle meets Azur Lane, Arpeggio & Haifuri

Kijima-san & Yamada-san - MangaDex

Youkai Gakkou no Seito Hajimemashita! - MangaDex