Conversation so far:
Where was Ai Born?
Ai was born in Los Angeles in 1981.
Where did she grow up?
She moved to Kagoshima in Japan when she was 4, and went to elementary school and junior high school in Japan.
What college did she go to?
CANNOTANSWER.

Question: What is SX4?
Self-contained rewrite: What is SX4 in relation to the singer Ai?