Day 23: A crazy love triangle/quadrilateral that worked out great.
Peter Burke/Elizabeth Burke/Neal Caffrey-White Collar.
I basically reject the premise of the question. Triangles suck. If there's competition, someone is going to get hurt and it won't end well for someone. The ONLY reason this works for me is because it's clearly NOT a triangle. Peter will never leave or hurt El. El does NOT feel threatened. IF anything were to happen, it would basically have to be OT3. One reason I like this fandom, is that even the hardest core slashers do NOT seem inclined to wage ship-war. So lets consider this a triad, rather than a triangle. Obviously they'll push the subtext as far as they can, but not do anything canon, so the "working out great" exists only in term of the on-screen chemistry and the positive attitude of the fandom.