quince
榲 refers to the quince fruit or tree. It is a specific botanical term with no broader conceptual extensions.
榲 is a phono-semantic compound: 木 (tree) provides the meaning, and the right side 昷 (a container with a lid, now written as 日 over 皿) likely contributes the sound. The exact historical development of the right component is uncertain.
A tree (木) bearing a fruit that looks like a small covered dish (日 over 皿) — that's the quince.
For オツ, imagine an otter (オツ sounds like 'otter') climbing the quince tree to steal the fruit.