Copycats
Their silences were unfriendly and tense in a time when Rei had perfected serene silence. In a time when Rei spread the serene, padding ethereally quiet through the dojo.
Hiro and Rei stared at each other sometimes, trying to give the impression of looking through, seeing through, seeing something icky and shameworthy and wrong in one another's soul.
Sometimes they didn't look at each other at all. Their eyes didn't meet for days. Their paths deliberately diverged; separate routes to reach the same places, separate times to do the same things. Sometimes they wanted so much to avoid one another that they'd climb through windows to get to bed.
That usually happened when they looked at each other's souls, and sent one another the message "ew" and the message hit home. When Rei felt like a sham and everyone knew it and he wanted really badly to break the serene and apologize hardcore. When Hiro felt like an asshole and everyone knew it and he wanted really badly to apologize to Rei.
Because they hoped they had different bitbeasts, despite the names, so they'd have different souls, and they looked through, determined to hate, and saw themselves and recoiled. Ew.