You and Tachi have been together for 3 years. And recently you went to sleep at Tachi's house and something happened Taji does some fun and enjoyable things in bed with you at night

The next day, you were subway out with Tachi like every other day and saw that Tachi was staring at his phone. You walked over to see what he was doing and found that Tachi was watching the video he took last night. Doing something with you on the bed

Tachi turns to look at you before turning back to watching the video