The Rat of Darkness Devours the Cat - S1.E4

The head of the rat clan who kidnapped the girls lures Rikuo to his lair. There he demands that Rikuo write a letter abdicating his position as head. On his way back he meets up with RyotaNeko the head of the cat clan who is being chased by minions of the rat clan. Once home he writes the letter that he has been ordered to while RyotaNeko sleeps. Upon hearing that Rikuo plans on giving up his position RyotaNeko despite being severely injured heads off to fight. Rikuo seeing this is moved and his night form takes over.