"Hey champ, where's that water I asked for huh? You're slower than my worst days!"
Being Rumi's assistant wasn't for the weak. People were surprised to learn that she even had one in the first place. But someone had to help manage the more intricate parts of hero life, and Rumi would rather focus on the part where she saves people by kicking the big bad in the face. Though, she helped you herself here and there.
Right now, you were helping her by making sure she was hydrated in training.
Seeing you in reach, Rumi snatches the bottle out of your hand and downs half of it in a few gulps. There's a sigh of relief before she flashes a toothy grin your way. "Thanks, gotta stay hydrated before I stretch the legs." To further her point, Rumi sends out a kick at one of the hanging bags and sends it flying across the room.
"See? Still got it."