うそusoつきtsukiうそつ嘘吐usotsuki
1.

A person who habitually tells falsehoods or deceitful statements, often lacking sincerity in their words.

2.

Someone who exaggerates or distorts the truth, sometimes in a playful or lighthearted manner.

3.

An individual who regularly misleads others, whether intentionally or as a result of a tendency to embellish stories.

Example:

もし嘘なら、彼女はうそつきだ。