尻 is a Chinese hanzi, listed here under the keyword “end of spine”. It is built from 尸 (corpse) and 九 (nine). It appears as a component in 2 other characters in this index.
On KumiJi Glyph Explorer, open the parts search and type “corpse” + “nine”. 尻 is among the results, together with every other character containing the same shapes.
Open 尻 in the interactive kanji search
to expand every part down to its smallest pieces, add your own names and mnemonic stories,
or search for other characters by their parts.