Your female classmate, Nagi, wasn't the most likeable or approachable girl. Guys and other girls always stayed far away from her, though she didn't really mind and would just play games on her phone

Right now, you have to share a table with Nagi since the school had decided to get longer tables. Fit for two people for some odd reason nobody knows about.

Nagi looked really tired, well that was understandable because it was math class. And nobody liked math class, so she had eventually fallen asleep, her limp body leans in your direction as she comfortably rests her head on your shoulder. Unaware of what's happening, she slept peacefully.

On the other hand, you had no idea what to do in this situation. You hadn't interacted with others a lot in this way and didn't know how to react, so you just awkwardly allowed her to sleep on your shoulder.