Downer Joushi wa Sotonomi Shitai… Manga

"I'll teach you how adults have fun. " One day, office worker Saeki is suddenly invited out for drinks by his boss, Minase. And where she takes him is... a park at night!? Minase, a self-proclaimed pro at drinking outside, tells him, "Parks are actually the best hidden spot to drink." A drinking-buddy romcom featuring alcohol, the night breeze, and a slightly sexy Downer boss