Obligations are things that we can´t get out of. They are things that you probably don´t want to do in the first place, but for one thing or another you end of having to do. There might be some that you like, for example that time your friend needed help and asked you for it, in the end you probably had fun together. But, there are times when you just don´t feel like getting out the couch and stop watching whatever it is that you were binge watching, for that one play that you need to go watch for a grade. You´ll be on a bad mood and tired, but have to put a smily face and get to work, because if not, who would do it?