There has always been a degree of darkness and self-center-ness to the character of Jack-it comes out in the beginning of S1 and is carried through to S3. I, for one, love the darkness and complexity that is seen in Jack.

Your point of him being demanding, somewhat abusive in addition to a whole lot of crap to Ianto is reasonable (everyone has made good points in this discussion).

I see the relationship between the two men as dysfunction, co-dependent since both are a bit fucked up. Their relationship seems to feed something they both need-face it to work for TW, you have to be fucked up to a point.