Objectum-sexuality is defined as the love for, and sexual attraction to, inanimate objects. This is not extremely enjoying your favorite vibrator, this is a full-blown love affair with such things as buildings, computers, trains, bridges, cars, and nearly anything else you can imagine.
Objectum-sexuality can loosely be compared to animism, or the belief that everything has a soul. For most objectumists they first fall in love with the "personality" of the object and then pursue the sexual aspect of their love. The sexual aspect is sometimes hard to accomplish, however, as it is hard to have sex with a building without getting naked in public, which is against the law. This has lead to some people constructing a model or miniature of the building in their home enabling them to make love with it as they please.
The birth of objectum-sexuality is credited to Eija-Riitta Eklöf-Berliner-Mauer, a Swedish woman who fell in love with the Berlin Wall upon its birth in 1961. The two became "married" to each other in 1979 by Mrs. Eklöf-Berliner-Mauer and it was a joyus day indeed. However, her heart was torn to pieces ten years later when her husband died on November 9, 1989.
More recently a story has turned up that involves a homosexual man from New York, Mark Allen, falling in love with his PowerMac G3. At first this started off as a relationship that Mark Allen had with a cyberboyfriend. The two would have candle-lit dinner together with the use of a webcam and eventually "slept" together using the same methods as the dinner dates. But when the two met in person their relationship fell apart. That is when Mark Allen realized he was in love with his Macintosh and not a human being.
Another popular objectum-sexuality type thing is the art of having sex with a car. But that is WAY beyond the scope of this writeup.