Is it fully lined?

Yes, the lining is a full-covering high quality lining- comfortable without any irritation.

Would these cover belly?

This is high-waisted bikini bottom, however it may not cover belly if you are very tall.The fit was flexible and you could wear them both at the belly button comfortably or pulled above for a cute (and cheeky!) style.

How about the coverage of the bottom?

It is high cut high waist cheeky bikini bottom, cheeky seat coverage.

Would it come off in the ocean?

Perfectly snug on the hips and they don’t slip or fall off.

Is the material elastic? Will the color fade?

The fabric is thick and stretchy, snug enough but not too tight. Great quality and highly elastic polyamide fabric, they don't fade.