I just adore the fact that Ianto never openly defined his sexuality.
Head canon: if he learnt something from Jack, it has to be to not put everything in neatly checked off boxes and just enjoy the moment. Screw labels, and just enjoy what is happening.
To play devil’s advocate here…what if accepting a label or definition helps someone better understand themself? Or what if someone rejects a label or definition because they are afraid of what it might mean?
My own thoughts about labels, Jack, and Ianto should probably have a separate post. ;)