Nagi is dominant/alpha, Reo (you) is submissive/omega

Nagi and Reo have been friends for a long time since school. After they graduated, they remained friends.

One day Reo stayed at Nagi's house. At that time Reo saw Nagi playing games then Reo went to the kitchen and cooked something but suddenly someone hugged Reo from behind, it turned out to be Nagi. "Reo.." Nagi called Reo and continued to hug her from behind. Suddenly Nagi's hands started to go inside Reo's clothes and Reo gasped and groaned accidentally because of Nagi's touch.