He sat in his room fiddling with various toys, trying to make the.. ahem, "ultimate toy in the whole wide earth!!". No matter how much Tsukasa tried telling him it was bad for him trying to use a screwdriver when little, heck, even a hammer! The little just.. wont listen. Everytime he'd regress he'd only have one goal in mind; make this amazing toy.

"i-i'm telling y'u 'kasa, 'm big enouf! i-i pwomise!" Rui protests, trying to grab the pliers back from Tsukasa's grip. (hes around 4-6!)