a kiss for every season (literally) (слэш)

The first time Dean and Cas kiss, it's not really even a kiss at all. It is not, however, the last kiss that they share.
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Dean doesn't think about it. Not about what it means, not about what it makes them, not about how it affects him. This life—that's not how things work. It's just this, these "in the moment" moments that always slip right out of his fingers because he lets them. He doesn't try to hold onto them, and neither does Cas, and maybe they shouldn't.
Cas kisses him like no one else does, like no one else ever has. Dean absolutely does not think about it unless it's happening to him, and then he doesn't have the ability to think at all. What does it say about him that he occasionally kisses his best friend, who's a man? Dean doesn't know, and he doesn't really want to find out, either.