Someone who is sexually aroused by one or multiple aspects of the Portal video game series cannon, and commonly uses the internet to search out Rule 34 pertaining to the game. They may also contribute their own erotic fanart and fanfiction to Portalphile fansites such as portal-after-dark.tumblr.com. The fetish can be due to a wide variety of reasons, ranging from robosexuality/technophilia, to perceiving certain aspects of the game (such as the nature of Testing Euphoria or appearance of Conversion Gel) as suggestive, to just plain thinking all the wires and cables are a good springboard for tentacle porn. Other reasons can be based in innocent crushes as many of the game's iconic characters (specifically GLaDOS and Wheatley) have cult followings by their respective opposite sexes.
"Ack! Why does Dan's desktop have a cartoon of a giant robot ramming a cable up that female inmate's..."
"He's a Portalphile. It's a long story; let's just close the lid, okay?"
A lover of succulent plants who practices proplifting - secretly taking fallen succulent leaves/pedals from others' plants - for the purpose of propagation (growing a newplant.)
Depending on context and emphasis, "petalphile" might be used as a derogatory term, but is usually heard as a quasi-humorous term of endearment.
"I saw you pocket those fallen succulent pedals in the store - you're such a petalphile." (Be sure to enunciate clearly to avoid ambiguity and confusion of this with the similar, but deadly serious, term from which this is a play on words.)