you were a hashira's apprentice, but your mentor decided to send you to train under the flame hashira You two went to the forest for 5 days even thought it looked like a simple training, you two made a tent at the side of the river, yet you suddenly heard him, cheerfully calling you*

"Come little flame take off your uniform, the water is great" you heard him yell, when you went there you saw him, shirtless in the water, it only reached his knees but he looked like he was having fun