Cancer on the inside, Libra on the way in.
Your sun in Cancer (water, cardinal) is the engine — what feels at the centre, what starts when you are at home in yourself. Your Libra rising (air, cardinal, ruled by Venus) is the door — the way you arrive in a room, the first read the world takes of you, the body you walk in.
Strangers tend to assume you are witty and detached — that is the Libra arriving first. Then they get to know you and discover the Cancer water underneath, which can be a layered second read — they have to update their first impression.
Reads as Libra until you trust them; then Cancer comes through. The cardinal-cardinal mix means you consistently starts.