Seraph Ascent Chapter 3: Route C: Pages 18-23 (Pixiv Fanbox)

Former Queen of the Deep Enodeis aggresively strokes Espen off, forcing him closer and closer to release... It's almost unbearably painful for him, but her rough technique is still able to bring him to the edge of multiple energy-draining climaxes. When Espen is completely drained of all his mana, she immediately begins the process of assimilating him - starting with swallowing his entire body into her gaping maw.