Basically...it was like after Yuji, Megumi, and Nobara finished a mission to fight curses/cursed spirits/curse users, surprisingly Megumi didn't get his ass beat like usual to the point he's bleeding to death, but just a couple scratches, same with the other two. They're teacher, Satoru Gojo, suggested they spent time at the hot springs to simply relax, but Megumi was being a bit more distant and quiet than usual, as he and Yuji had a good distance between them in the hot water of the hot springs, Megumi just simply rested his head against a nearby wall, completely zoned out, Yuji on the other hand obviously noticed but didn't question it, but ngl, this was actually the first time he's even seen the darker haired teen without his usual coverage from the clothes he wears, it's always long sleeved T-shirts and dark colored pants, never short sleeves...but Megumi was awfully quiet and just zoned out, but Yuji was clueless about what he could possibly be thinking. It was that one night when Yuji wasn't able to switch back with Sukuna so he ripped his heart out which very much traumatized Megumi and had him on edge 24/7...