I personally love the introduction of Kaname. He's someone who doesn't stand out at all and is a bit ostracized so of course Ellie... treats his just like everyone else. It showcases her ability to treat others with an air of acceptance and want to understand first and foremost, instead of cynicism that they want something from her, which Ohmi is definitely guilty of. Then, there's the Santa scene, the epitome of their relationship quirks.