cling to, cuddle, embrace, fondle
偎 centers on close physical affection: clinging to someone, cuddling, embracing, or fondling. The meanings all share the idea of holding or being held in a warm, intimate way.
偎 combines the person radical 亻 with 畏, which likely contributes the sound and may relate to the idea of closeness or fear, but the exact historical development is uncertain.
A person 亻 beside 畏, which looks like a head above clothing. Picture someone snuggling close, wrapping themselves in another person's clothes for a warm cuddle.
For ワイ, imagine a couple cuddling and whispering 'why' they love each other: why -> ワイ, as they cling together.