Xbooru - 2010s 2019 2boys animated skeleton big dom big dom small sub bigger dom bigger dom smaller sub biting neck blue flower boots bottom sans brother brother/brother brother and brother brothers clothed duo echo flower flower fontcest foreplay ganzooky gloves hoodie imminent sex incest male male/male male only monster nsfwsinningsans outdoors papyrus papyrus (undertale) papysans plant red boots red gloves sans sans (undertale) seme papyrus shirt lift shirt up skeleton small sub small sub big dom smaller sub smaller sub bigger dom top papyrus uke sans undead undertale undertale (series) unseen male face