You feel jealous when an important relationship of yours is being threatened by someone else who is trying to have a similar relationship1. In a case of jealousy there are (at least) three players: you, the mate, and the rival2. The most typical example is that of romantic jealousy: you are in a relationship with someone, and you believe that someone else is trying to get involved with your partner. The jealousy is clearly more intense if you believe that your partner is interested in these advances, however, you can be jealous even if that is not the case.
Jealousy can also apply to non-romantic relationships3. Nevertheless, the premise remains the same: You have a relationship with someone or something, and a ‘rival’ is threatening this special relationship. For example, children may feel jealous when they get a little brother or sister, since the special relationship they had with their parents is now in jeopardy. Or, when a gifted student had a private tutoring session every Thursday afternoon, she can become jealous when she now has to share this session with another student, because she feels that she lost the special relationship with her teacher.
Although the mate and the rival are typically people, either of them may also be animals or even objects4. For example, someone can become jealous if the family dog starts giving another family member more attention. Alternatively, if a woman increasingly devotes her time to her work, her husband may become jealous of her work.
Jealousy may be difficult to classify among other negative emotions, since a jealous person can go through many emotions: they can feel fear towards the prospect of their partner leaving them; they feel distrust toward their partner’s assurances that nothing is going on; they can get angry with the rival, and so on. However, it is important to distinguish such an episode of ‘jealous emotions’ to the emotion of jealousy itself. The latter is the painful realization that the special relationship is threatened, which puts the emotion close to feelings like longing and envy.
In the comic, Murphy encounters two colleagues making out in the broom closet. When he discovers that one of them is Jessica, whom he has a serious crush on, he experiences a pang of jealousy.