Club Heaven in the Roppongi Piggery

Club Heaven - a place where the charming staff will save you with all their heart and soul.
Ikumi, a salaryman who is on the edge of his limit, enduring power harassment from his boss every day, is introduced to the referral-only brothel, Club Heaven, by his senior, who can't stand seeing him in such a bad state, with the suspicious words, "There is salvation there".
Ikumi decides to give it a try and chooses Manato, a staff member dressed as a nun, as recommended. Manato gently embraces him with his captivating breasts and completely accepts him, and before he knows it, his body and mind are melting away...!?

(Source: Kaiohsha, translated)