He could hear the muffled shouts of "I'M HOOOME, CHILDREN!" echoing through the hallway. Ichigo tried to back into the narrow space under his bed as he heard the footsteps coming closer. "Take it slowly," he muttered to himself under his breath as he tried to wedge his shoulders under his mattress. "One step at a time… almost fits… there we go… "
Ichigo felt a sharp jab in the stomach. "What are you talking about now, idiot? You pervert!" He flipped around to try to see who the voice belonged to, even though he already recognized it. Instead the side of his head banged into the metal bedframe, and the whole structure shuddered loudly. He prayed his father hadn't heard it. "Damn, Rukia!" he whispered back behind him. "Shut up! Why the hell are you even here?"
"I live in your closet, stupid."
Ichigo could hear his father's humming draw closer and held his breath. Please don't let that door open. As he visualized the doorknob turning, he instead heard the footsteps stop. "Yuzu! Come here!"
Well, shit.
"Yuzu!" Quieter footsteps ran up to the door. "What is it?"
"Look how Ichigo's door is closed! That can only mean one thing."
"What, Daddy?"
"Did you see Rukia today?"
Ichigo drew a sharp intake of breath as Rukia's sharp elbow crashed into his side.
"I think I saw her coming out of the high school today. But I don't know if—"
Isshin laughed manically. "Let's go, Yuzu! It seems like Ichigo is having some fun time in there." The footsteps subsided and Ichigo turned around to see Rukia, bright red and glaring hard enough to scare away an army of Arrancar.
"What the fuck was that about, Ichigo?"
"God, it's not my fault that I have a pervert for a dad! Ugh, what are you doing? Get your hand out from—hey! HEY! DO YOU—"
"Of course I do. Shut up and take your pants off, idiot."
Outside the door, Isshin crouched, a glass pressed to the door, transcribing the results of his experiment onto a small notepad. He snickered to himself, fingering the tip of the pen as he wrote. Masaki would be proud.