Yakuza ga Tensei Shitara Mori Ranmaru Datta Ken

Young mafia boss Hajime thought he was shot and killed by his enemies... Until he snapped into the world of the Warring States period! When the one and only great Nobunaga Oda takes a liking to him, Nobunaga renames him Ranmaru Mori for some reason, but that isn't Hajime's biggest shock. Nobunaga fondles him all over, kisses his neck, and forces himself into Hajime's untouched parts. Frustrated as he is with his domination, Hajime can't stop moaning. Turned into a Nobunaga's subordinate, what will become of Hajime? (Source: Renta!)