So, the male lead discovered that the school nurse was out and went inside himself. Dizzy and muddleheaded, he picked a bed at random and flopped onto it.
By this point, you readers already had a picture in your heads. The male lead wasn't alone in that bed. For some unspecified reason involving feeling unwell, the female lead was resting in the Nurse's Office, and they just happened to end up lying together.
Even though the male lead had knocked earlier, the female lead lying in bed simply hadn't heard him.
At this point, forget about plot logic. Nobody watched scenes like this for logic. The audience knew perfectly well what they wanted...
Then, to create contrast and some awkward, innocent humor, the shot would freeze for a moment. The leads would stare at each other, stunned, or casually exchange greetings before either had registered what was happening.
The next second, the shot would cut to an overhead view of the entire building, with the leads' screams as the background sound effects. The outdoor camera angle emphasized just how loudly they were screaming.
That was the general outline of a Nurse's Office story, and also the most basic version, with no viewing age restrictions.
If the school nurse suddenly came in next, leaving the leads no time to separate, the male lead would pull up the covers while the female lead hid beneath them to avoid discovery. That would take the plot's depth up a notch.
Conversely... if the female lead stayed outside while the male lead hid beneath the covers, given that girls' uniforms in anime mostly featured short skirts, the plot's depth would rise another level.
In the brief climb up the stairs from the first floor to the second, Shen Qi had already simulated a whole host