The Curious Chemist Mouse is only attracted to Gnarled Cheese. I think it eats a nibble and uses the rest to prepare the Wicked Gnarly Cheese Curd Potion. You'd need to catch more than a dozen of this, to craft the Wicked Gnarled Cheese.
The mouse appeared pretty late in the game so most of us already have lethal and lucky physical traps like the chrome drillbot. If you're currently Master/Grandmaster, do drop a comment here on which trap worked for you.
This resident of the Great Gnarled Tree loves to combine different compounds that it finds in nature with cheeses that it pilfers from traps. An avid amateur chemist, it mixes up some seriously strange potions- things that turn fur purple, and make ears grow to ten times their size. No one knows what the Chemist's latest potion does, or why it is suddenly seeking large amounts of Gnarled Cheese and SUPER|brie+, but one thing is for sure: the results are going to be Extremely Gnarly.