This particular fetish finds its place in the numerous paraphilias examples (sexual arousal using objects) and the people that enjoy this fetish are called most commonly "looners". The whole point is inflating balloons of different sizes (and in this case, size matters) until they pop. This is done by using mouth only, although in case of really big balloons, other form of inflating are necessary.
"Looners" are divided in two categories: poppers and non-poppers. The non-poppers take their pleasure from the process of inflating the balloons, their size and shape and most often from the physical stimulation of these object held against their bodies. This category puts an end to their fun when the balloon pops. Poppers, as it is logical, have their arousal increased by the suspense of inflating a balloon and the culmination comes with the ultimate event, the burst of the balloon.
On a psychological level, it's not easy to understand the attraction towards a balloon-popping moments, since many people are afraid of the moment a balloon pops and no pleasure could be reported from the resulting noise and palpitation. For Looners this is a big joy and the rush comes from association with early childhood experiences which at that point were fearful but now became eroticized and "translate" into an irresistible arousal.
Depending on the circumstances from which this fetish is metamorphosed after the puberty experiences, the looners may regard balloons as an essential part of the sexual experience, either by popping them in which case this is considered as a metaphor for orgasm, either avoiding the popping at all costs, in which case the popping it's a metaphor for death.
The community for this fetish is very numerous and though some of them have the need of tactile experience, others will say that their pleasure comes from watching others playing with balloons, popping them or just inflating them. In the world of fetishes, balloon loving is one of the most softcore nature and Looners do not respond to balloon content associated with hardcore sex.
Balloon popping can be the subject to several party games, and Looners enjoy the adrenaline rush associated with the imminent "danger" from which the popping will produce a sexual response. This also explains why even the non-poppers who fear the burst moment and develop a phobia for this may actually be aroused by this possibility in safe sexual context.
There has been a connection made between balloon fetish and latex fetish, since like latex, balloons are tactile and supple and imitate pretty well the human skin. The ability of expansion is the representative part of the swelling of primary and secondary sexual members during excitement and arousal.
In terms of using a balloon as a sexual toy, many Looners like the touch of these objects against their naked skin and the rush given by the possibility of a burst can be the reason for a powerful orgasm. It's a frequent practice amongst the Asian mistresses who take advantage of these features and like to "torture" their submissive using inflated balloons. The sexual stimulation comes from the balloon itself and from the way it's used, but other stimulants can become handy (such as sharp objects threatening the balloon).
It's not unusual for some to consider a balloon as an entity itself and to keep it for days, involving it in their sexual games, considering it a sexual partner. This could go on until the very end of the balloon and only non-poppers proceed this way. For poppers it's well known amongst Looners that the popping in its nature represents the release of the sexual build-up.
Communities of balloon lover have been formed since the 70s and they have grown stronger on the internet starting 1993. Even though this fetish seems more likely to take place in offline groups, the online is still the biggest environment in which they meet and share their experiences, videos and images. There is no sexual orientation required for balloon fetish buddies, they can be straight, bi, gay and they only need to have this love for balloons in common. As a safety tip for them, all communities of Looners recommend using eye and ear protection when it comes to large sized balloons.