This was just an excuse to play around on Pixlr. And Rainwilow is Bi. The profile drawing is WAY less pixelated in fullscreen. I tried to export this with maximum clarity; everything looks fine except for this ONE part!
Chrome Canvas for background, cats, and heart color (but not the shape). I used Picrew (who knew there would be FIVE Warrior Cats makers on Picrew?) for the design of the drawing of Rainwillow on the right. Pixlr (a photo editor) for arranging everything, the text, making slight changes to the designs, and being awesome to the point that it rivals Photoshop. (I've never used Photoshop, but Bright Guardian Akira uses it in her OC fix videos). Google for the ThunderClan symbol.
