How many pieces of swimsuits are there?

Only bikini top, no bottom.

Is the bra of the bikini top removable or built-in?

The bikini top has a removable padded bra.

Is this bikini top has fully lined?

This bikini top has a full lining design and will not be seen through.

Is this bikini top comfortable?

It is very comfortable to wear and is made of soft, elastic and breathable fabric.