Sorry, I'm not very familiar with the specific 'ulala session love fiction' song lyrics. You can try to search for it on music platforms where you might find detailed lyrics explanations.
You could also check on social media platforms. There might be fan pages or groups dedicated to 'ulala session' where fans share and discuss things related to the band, including the lyrics of 'love fiction'. Additionally, YouTube music videos of the song may have the lyrics in the description or as captions, which can be a convenient way to access them.
Since I don't know the exact 'jo tu chahay' story, I can't say for sure about its origin. It could come from a local tradition, an individual writer's imagination, or even be part of a specific cultural movement in a certain region.
I'm afraid I don't know much about 'De Ijazat Jo Tu' novel. But you could try looking for reviews or summaries online to get a better idea of the story.
There are many stories and works out there, and 'jo tu chahay' doesn't immediately ring a bell as a well - known universal story title. It could be a name of a story from a certain area, a personal project, or something new. Maybe it's a song title that has a story behind it? Without more context, it's difficult to tell the full story.