If you really want a summon, then I would suggest Gamakichi. (The orange frog.) He chases repulse and causes repulse so it doesn't really change your combo there. It just adds a little bit of extra damage!
Personally, I would get the White Tiger Pet, which chases High Float -> Repulse. That would create a loop with your skills and your pet, assuming that you're using the correct Main's skills.