Pterosaurs had fuzz, and a nice portion of dinosauria had fuzz(Early/ primitive theropods ) and/or feathers(Maniraptorans, including aves/birds, deinonychosaurs which are raptors, and even a nice portion of tyrannosaurs,ornithomimosaurs,and therizinosaurs) and quills(Tianyulong and potentially ceratopsians).
Baby T-rexes had fluffy feathers that thinned out as they grew. So cute!