Thanks for the comments people
The little guy is part of the house hold here. However, it is troubling and I have to reevaluate my lifestyle due to this since I'm a frequent traveller and often away from the apartment. Fortunately, my neighbour is awesome and has taken care of him and has experience with diabetic cats.
I took over ownership of him after my former roommate had to give him up due to family reasons. He has certainly grown on me this past year. I still ensure he gets the best care in the mean time. I'm just freaked out right now on the added responsibility and extra financial contribution needed