Majokko Mariel'n

Main character is a ronin student. If he fails to enter university this year he'll need to inherit his family ramen shop.
One day he meet again with his junior high school first love Iori and reunites with her. However, on another day a girl comes down from the sky on a broom and she is followed by another girl. Hero is caught up in a dispute, and turned into a small animal (ferret) by the magic. The first girl escapes and second girl Mariel, remains. Mariel explains the circumstances - he has to live in this form for a while till she finds a way to dispel the magic.

[From vndbreview]