I ran straight for my old Here Kitty Kitty set from 2007 - still a goodie! I kept things VERY basic for the CAS brief, but also did slightly subdued colors, thinking this would be a good one for a boy, too... I love all the choices we have in our Blender pens, lol. And I knew kitty felt like playing with his mechanical mouse today - that's what you do on a birthday!
Here, Kitty Kitty Stamp Set (retired 2007); Basic White CS; Memento Tuxedo Black Ink; Cajun Craze, Smoky Slate, Just Jade & Pumpkin Pie Blends Markers; #ATC215.