The title says it all. Clicking on these things is nigh impossible, and if you haven't figured out you can hit a key press to pick which action in the menu you like, it's also nigh impossible to effectively massage + milk them. I've been close to dying because of the effort it took accidentally singing to a butterfly.
The menu for the butterfly should also not bounce around despite the actions of the little insect.
Bonus suggestion: an item which makes butterflies amble near you when they're within a certain radius. Something you create with a beaker perhaps. Something like...Butterfly Love Potion No. 9
:)