Good Night.
Based off that small part in volume 10 of the manga, just after the Devil Bats reach Vegas and finish the Death March.
Hiruma walked into the next room after yelling at and attempting to shoot awake his extremely exhausted juniors, who had flopped down on the comfortable hotel beds at first opportunity. Mamori had, of course, foiled the shooting attempt with a mop (somewhat to his irritation) and then shooed him out of the room to let his teammates get much-needed sleep.
Suzuna stared after him as he disappeared into the room, Cereberos bounding at his heels.
"Amazing Spartan," said Suzuna. "His physical strength is incredible…"
Mamori turned to look at the door. "Mmm… Yeah," she admitted slowly. Her mind flew back to the time during the Death March when Hiruma had gone round to one side of Doburoku's truck and sat there with his trusty laptop. She had followed him and perhaps for the first time got a real insight into the team captain's character. (The devilish part of him didn't count – that was obvious enough to the whole world.)
Alone in the dark sat Hiruma Youichi, coolly doing some probably suspicious stuff on his laptop, his right pant leg rolled up above the knee and hand resting lightly on his knee. There was enough dim light from the laptop and from the lights on the other side of the truck for Mamori's keen eyes to see the injury on his knee.
The scene made her think. Why did he choose to be alone and endure his injury alone like that? Why didn't he let the others know? No one else hid their bruises or blisters or cuts or aches. Some of them were more vehement than others in complaining, even. But why did Hiruma – the loud, sneaky, sometimes arrogant boy – want to be alone when his teammates were all around him and all in the same boat too? Why didn't he allow himself to relax a bit?
On impulse, she went to him, First Aid kit in hand. She knelt and started pulling out bandages. He had been surprised to see her, although surprise only showed faintly on his face. He'd told her to "go look after the brats" but she had refused, insisting that he let his injury get some treatment. He did eventually allow her to bandage it, but true to character, he gave her a hard time of it, shaking his leg when she told him to keep still.
"Ah!" Suzuna exclaimed. Mamori snapped out of her short reverie. "I have to ask my brother about the places he passed and what happened…"
Taki's sprightly sister made for the still-open door of the room Hiruma had just entered. A thought flashed through Mamori's mind.
"Suzuna!"
Suzuna stopped and looked questioningly at her.
"Do it tomorrow."
"Huh?"
Mamori smiled, feeling slightly sheepish. "I think the boys need some rest. You can ask Taki-kun tomorrow."
"I guess..."
While Suzuna took a bath, Mamori slipped out of the room to check on the team. A quick peek into Sena's room showed her Doburoku seated in a chair whilst the sleeping boys were sprawled in various attitudes around the room. Doburoku gave her a thumbs-up and she closed the door again after murmuring good night to the stocky trainer.
The door of Hiruma's room was still open so she looked inside. Kurita occupied one of the single beds and was snoring away. Taki lay on the floor, a strangely happy look on his face.
He must be having a good dream, Mamori thought, amused at his expression. She glanced up from where Taki was and saw the thin, black-clad figure just where she thought it might be. She couldn't help a small smile. I guessed as much.
On the other bed was none other than the feared Hiruma Youichi, looking much less fearsome than usual in sleep, his feet dangling off the end of the bed. Only the gun at his side was a reminder of his dangerous behaviour.
For all his evil reputation – which she couldn't refute – he really did work hard and try his best. Maybe… Just maybe, she thought, Hiruma kept to himself so much because he didn't want to worry the others. Because he was afraid that if he showed weakness, they would lose respect for him (and fear) or, they would lose confidence in the team. Maybe as captain he saw it as solely his responsibility to keep the team going. Maybe he was just proud too.
There were several possible explanations for his wanting to hide his weaknesses, his injuries. Whether all her guesses were right, or whether they were wrong, she knew one thing – the demon captain of the Devil Bats could be vulnerable too. And it didn't make him any less a leader. She doubted that knowing he was imperfect would affect the opinion of the others at all. She wished he knew that. Maybe then he'd lighten up a bit, be less evil and trigger-happy.
Seeing that the window curtains were wide open, she drew them shut so that the bright lights of Las Vegas wouldn't disturb the boys, although she figured they probably wouldn't wake up even if she shone a spotlight directly into their faces.
She left the room, whispering "good night" as she had in the other room, and closed the door as quietly as she could.
When the door shut, Hiruma opened one eye just a crack, faintly registering that those annoying flashing lights were now shut out of the room and mumbled under his breath, "Thanks… Stupid manager."