Vanity — the desire to show off or be seen favorably by others; pride in appearance or reputation.
彼は虚栄心が強く、新しい車を買って見せびらかした。
He was very vain and bought a new car to show off.
虚栄心のために無理をして借金をした。
He went into debt because of his vanity.
有名になりたいという虚栄心が行動の動機だった。
The motive for his actions was the vanity of wanting to become famous.