Serph, human-passing though he may be, is having problems of his own with the door. His own attempts aren't so much foiled by persistent crankiness as by a very new, still developing understanding of the production and display of emotion, in the first place. It's only very recently that the residents of the Junkyard began developing emotions, and more recently still that they started to acquire the vocabulary to name these odd, mysterious intrusions into The Way Things Always Were.

The idea of faking an emotion, or the appearance of one, is still very much a mystery. Serph's displays have always been more muted than those of his comrades, but also always genuine. His smiles are faint, fleeting - and have never once been anything less than a completely accurate reflection of his mental state.

So here he is, standing in front of the sensor, the occasional slight twitch in his features only making him look all the more at a loss, like he's not sure which muscles he's supposed to be moving.

He's not trying to be difficult about this!