In the episode “Black Hole” from season 6, House forces Wilson to buy a piece of furniture that says something about him: Wilson chooses an organ that House absolutely loves. House’s response is, “I like what this says about you.” To elaborate, in previous episodes Wilson got mad with Cuddy for hurting House and outbid her on the loft she was trying to buy. Then he moved in with House. House spent the entire episode pestering Wilson about furniture, going so far as to saying that if Wilson is incapable of buying furniture for himself, he’s empty inside. Cue Wilson nearly driving himself crazy trying to buy furniture and failing miserably; finally, he gives in and uses an interior decorator. The only thing in the whole apartment that Wilson actually manages to choose and buy on his own is an organ, which isn’t even for him, but explicitly intended for House. Implications are clear: House is the only fixed point in Wilson’s life, the only thing Wilson’s absolutely adamantly sure about, and he chooses to honour that. Frankly, this may be the most romantic gesture anyone on this show has made to anyone.