In Real Life
, bisexuality can span a huge spectrum, from being mostly straight to mostly gay to being pretty much equal opportunity. On TV however, there seems to be one particular breed of bisexuality that is dominating at the expense of all others: the bisexual character who sleeps with and has casual fling with both sexes, but they only get serious with one of them
. For example, Alice may have had sex with women in her past or dated them in college or high school, but as a married woman, all of that is firmly stated to be in the past. If still single, she might still be sleeping with women, but you can safely bet that she isn't going to fall in love with or settle down with any of them. The key here is creating a distance to one gender - it's almost like having a gay or straight character and then adding experiences with the other gender as an extra "spice" to the character. Usually it can be explained with the creators trying to take in some diversity in their cast without having to challenge hetero- or homosexuality as the norm in their world.
A character fits into this trope if they fulfill one or more or the following criteria:
1. They are only shown to fall in love with, or get emotional about relationships to one gender.
2. They only go into relationships with one gender
3. There is a clear difference in time perspective (the character used to date both genders in their youth or a long time ago, but are never seen to be doing so on screen)
4. Their sexual interactions with one gender are played for laughs
- Aral Vorkosigan in the Vorkosigan Saga is this kind of bi. As in: "Do you know your husband is bisexual? - He WAS bisexual. Now he is happily married."
- House: Thirteen is close to a perfect illustration of the trope, sleeping with women and using her bisexuality as titillation for her boyfriend.
- Captain Jack from Torchwood. While he does have some sort of relationship with Ianto, it's mostly ambiguous and at least one writer has interpreted it as one sided, not to mention that he has a Star-Crossed Lovers thing going on with Gwen throughout the series. While casual comments are made about past boyfriends, his more romantic memories are mostly with women.
- Ellen from ''El Goonish Shive'. Technically bi, due to the specifics of her creation, but eventually decides that she's basically just lesbian, after a traumatic 'dream'.
- Yugioh The Abridged Series does this with Joey Wheeler (who was straight in the original), giving him some bi-curious moments with other guys (Kaiba, especially), but he and Mai Valentine are clearly each others' love interests.
- In The L Word, Alice, Tina and Jenny identify as bisexual most of the time. But they are only really seen in serious relationships with women. One time, Alice did date a man, but he was a lesbian identified male.