This series is well-known to Indians under the Sanskrit name Vetala-Panchavimshati - which means "ghoul('s) N" which is short for "N (stories of the) ghoul [1]".

Pancha means 5, I forget or don't know what vimshati means - could be that the whole number part (panchavimshati) means 25.

So the whole name of the series means 25 stories of the ghoul (vetala) - as told to king Vikramaditya, a famous king of ancient times, on whose back a ghoul somehow landed, and who then had to carry the ghoul on his back from somewhere to the cemetery 25 times.

Each time, while going there, the ghoul told him a different story ending in a puzzle or question.

Vikram was renowned as a good and fair judge.

The ghoul would tell him each time, that if he answered the question right (which involved judging the protagonists of the story, and saying who of them was right or wrong), he (the ghoul) would get off his (Vikram's) shoulders and let him go. But, if by the 25th time, Vikram still did not get the question right, the ghoul would kill him.

Entertaining stories we heard or read as kids. Often with some moral. Typical of Indian legends / folk tales.

[1] https://en.wikipedia.org/wiki/Ghoul

Edited for better wording / typos.