Imu basically seems to only care about his past acquaintances and their modern parallels (Davy Jones, Nika, Nidhogg, Lili and for some reason Shirahoshi), he barely seems to register the rest.
Outside of the simping, I really have no idea how Imu will react to her. I wouldn't be surprised if started crying tears of actual joy, considering he was smiling fondly while calling Nidhoggr a traitor.
IMO, Imu is a classic villain that got what they wanted, and can't admit that they kind of fucking hate it.

