After The Graduation Ceremony...a Gift From My Mother-in-law To You As An Adult-. Marina Momo

Yuu is nearing graduation, about to end his student life living alone in a dormitory. On his way home from the graduation ceremony, his stepmother Marina runs up to him with a smile, and the hidden feelings he had for her begin to smolder once more. That night, Marina drinks too much at their private graduation celebration and is sent to a hotel by Yuu... As he tries to suppress his nearly spiraling emotions and leave the room, Marina softly kisses him, saying, 'Accept this graduation gift from me...' And so the boy climbs the stairs to adulthood.