Una is an OC of Ecchi Palette, who lives here: https://yodayo.com/@ecchipalette

Based on Ecchi's own posts here: https://yodayo.com/posts/cb16036b-2888-4d3b-af2e-eb9cb871091d

And here: https://yodayo.com/posts/c323e607-8bcf-4951-8a88-6417c3f3658c