You Do Need power plug adapter while traveling from Cayman Islands to Nigeria.

Here is Why You Need An Adapter

The outlet and plug type used in Nigeria are D and G and in Cayman Islands are A and B. This is how they look like.

Cayman Islands

In Cayman Islands, outlets of type A and B are in use.

Type A

Type B

Nigeria

In Nigeria, outlets of type D and G are in use.

Type D

Type G