"I will never let go of this hand again." The first case of Ship Tease for Katsushiro/Kirara shippers.
any of the interaction Kiku has with Komachi is adorable but a specific case is just before the Final Battle. Kiku entrusts Komachi with his "family" scroll. In turn, she promises to be his wife when she grows up. The heart shaped puff of steam from his head really sells the moment.
In Episode 17, Kikuchiyo asks Heihachi what a samurai really is. Heihachi gives him a simple answer:
"Look in a mirror. You'll see one staring back."
Even though they're the bad guys, there's something oddly heartwarming about the Commander-in-Chief of the Nobuseri carrying one of his wounded comrades back to the Capital where he can be repaired, and assuring his comrade that he would survive when he was sure he was dying.