mostly depicting boys kissing or light making out.
shonen ai, as a medium usualy revolves around relationships and emotional situations, rather then the guy on guy sex.
Often, shonen-ai is associated with fluffy, cute, and cuddly relationships - but the term is not completely restricted to such descriptions. Occasionally, an author will turn out a darker portrayal of a relationship between two guys and use the term "shonen-ai" as a forewarning that romantic relations between the two should be expected, but there will be very little (if at all) explicit sexual interactions. Unless specifically stated otherwise.
Shonen-ai also corresponds with the term "slash" which has less of an emphasis on whether or not the relationship between the characters involved is romantic or entirely sexual. Shonen-ai's counterpart is shoujo-ai - "girl"+"love". And the corresponding term for shoujo-ai that's used in regards to explicit sexual interactions between two females is yuri. Shoujo-ai and yuri can also be called femmeslash - or, sometimes, just slash.
"Adrian and Lawrence are so cute as a shonen-ai couple and even if Adrian did killed Lawrence...he died in the end for Lawrence..."