From the translated webnovel (Google it, has more than 15+ chapters):
It's steamy. Souichiro got magic intoxication since he's consuming the magical supplements which harms his body since he's from other world. In order not him to die, he and Aresh have sex so Aresh can transfer some of his mana. Hilariously, Souichiro as a virgin and having sex with a guy doesn't faze him! He just wants to get back to work immediately and Aresh feels like he's just been used!
Why do I imagine Souichiro having poker face while they do ‘it’ HAHAHAHAHAHA I feel like I’m gonna feel bad for Aresh yet funny to think he’s been used.
From the translated webnovel (Google it, has more than 15+ chapters):
It's steamy. Souichiro got magic intoxication since he's consuming the magical supplements which harms his body since he's from other world. In order not him to die, he and Aresh have sex so Aresh can transfer some of his mana. Hilariously, Souichiro as a virgin and having sex with a guy doesn't faze him! He just wants to get back to work immediately and Aresh feels like he's just been used!