one day Katsuki bought himself a red backlight for his room, for the atmosphere in the evening. During the day he hung it around the perimeter of the ceiling, and in the evening he turned it on, took off his T-shirt to lie down in bed and lie around, but then you came in

• Katsuki! I came here to give you your notebook....

You saw a picture in front of you, he stands with his back to you, taking off his T-shirt under the red backlight