You’ve seen her in battle, you’ve seen her at work, you’ve even seen her being playful. Now you’re about to see Chikako being… graceful. She’s pretty skilled on her feet, and she knows a few moves that are guaranteed to impress. But why is she doing this?
Well personally, I like to imagine you (the viewer) have been treating her rather sweetly, and it touched her heart. I don’t bring it up much, but both she and Toshi were treated poorly by humans and yokai alike in the past. So receiving genuine affection makes her want to reward those who did so. I’ve got a character in my roster who canonically does (you’ll see that soon enough someday), but in the meantime just imagine that this is all for you.
Chikako: “Your kindness towards me is a much appreciated comfort. Allow me to share my gratitude towards you by displaying upon you a most sacred and elegant dance. My mother taught it to me, so I do hope that you like what you’re about to witness.”