second skin
noun1
Describing something which so perfectly suits one that one does not notice it.
- Near-synonym: one's element.
- "Hey!" Alex sputtered as soon as she got Clare's foaming wake out of her face. She knew she could still beat her even with the head start though. Water was like a second skin to her and Clare had only half her skill.2012, A Memoir of Love:
2
Describing clothing that is extremely form-fitting.