uru-uru（ウルウル）
uru-uru describes eyes filled with moisture, usually from tears that have not yet fallen.
uto-uto（ウトウト）
uto-uto describes the state of dozing off, drifting in and out of light sleep, or becoming drowsy without fully losing consciousness.
uwaa（ウワァ）
1. A drawn‑out exclamation of surprise or emotional reaction