Her gaze definitely drops to Mami's hand for a moment, and Madoka can feel her heart sinking. It feels like she said the wrong thing, but what else was she supposed to do? She feels like Mami would have freaked out for sure if she just dropped the information right away!

"Um.." Instead it makes Madoka pause now as her brain furiously tries to find a way to tell this that won't sound super suspicious. "Well.."

Okay, she can do this. Just avoid the c-o-n-t-r-a-c-t word!

"This is Maru. He's, um.. He's going to help protect me when there's fights, like during missions. And help me be able to fight if it's necessary." Yes, she is saying that somehow this tiny adorable cat will somehow be able to do that.