Looks more like Sumire than Mugi, no?

That's because it is Sumire.

They are so similar, anyway...

Sumire lacks Mugi's edible eyebrows, and she also has somewhat shorter sidelocks in comparison to Mugi (which I think is a trend of the author when cloning his characters, such as Azusa in comparison to Mio).

Welcome to the club, Sumire

The pussy is covered by the hand Azusa's hand. Tag removed.

Azusa is cheating yui!