coax
賺 centers on using words or charm to persuade someone gently: coaxing, cajoling, or winning someone over through soft talk rather than force.
賺 combines 貝 (shell, money) with 兼, which likely contributes the sound and may suggest the idea of combining or involving. The exact historical development is uncertain, but the character is associated with coaxing or persuading, possibly through material incentive.
The left side 貝 (shell, money) and right side 兼 (combine) suggest using a combination of money and sweet words to coax someone into doing something.
For タン, imagine coaxing someone with a tan (as in suntan) vacation offer: tan -> タン, and the promise of a sunny getaway helps persuade them.
to coax; to cajole; to humour (humor); to wheedle