Demisexuals are characterized by a lack of sexual attraction toward any person unless they become deeply emotionally or romantically connected with a specific person or persons. The level of connection it takes for sexual desire to form is dependent on how close the relationship is rather than initial attraction. It is an orientation that is not chosen.
Demisexuality does not refer to the active restraint or repression of sexual desires or actions.
Demi- is a prefix meaning half. This is used to mean halfway between sexual and asexual. The term originated in the asexual community, specifically within the Asexual Visibility and Education Network (AVEN).
Sexual partner: Hey, I think you are sexy. *aroused*
Demisexual partner: I'd have to reach a higher level of emotional intimacy before I could feel the same way. =\
Sexual partner: Oh, I see. Well, we can do something enjoyable together. =/
Demisexual partner: =D We can bake a cake for now!
Sexual partner: Sure! That's always fun, although we seem to be doing that a lot. =D
Demisexual partner: *squeee! bonding time!*