sacrifice
禜 centers on a ritual offering to ward off disaster: a sacrifice made to appease spirits or gods.
禜 combines 示 (altar, spirit) with a phonetic element that likely contributed the sound. The character is associated with ritual sacrifice to avert calamity.
The bottom 示 is an altar. The upper part looks like a complex offering being placed on the altar: imagine a ritual sacrifice to appease the spirits.
For エイ, picture an ancient priest saying 'A' (エイ) as he places the sacrifice on the altar: 'A' -> エイ, the sound of offering.