OK, if you know the building, I got 2 different sources translating, they say they wnt to the roof, but they went somewhere, wether it was the roof, staircase or outside balcony, it doesn't matter. They went out, and returned being clearly affected by drugs.
First time they went out, when they came back in, they just sat there, laughyng at nothing. Then second trip out, when they came back in, they sat there, stiring into the air, then they were sleepy, started to dooze off.
Could it be more obvious than this, without showing the actual drug?