The most common and most likely answer to this crossword clue is the 4 letter word PETS
P
E
T
S
More clues leading to the result PETS
Buddy explains!

The straight part
We know that "Mascots" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mascots = pets.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does PETS mean?
PETS noun- An animal kept as a companion.
- (by extension) Something kept as a companion, including inanimate objects. (pet rock, pet plant, etc.)
- One who is excessively loyal to a superior.
- Any person or animal especially cherished and indulged; a darling.
- To stroke or fondle (an animal).
- To stroke or fondle (another person) amorously.
- Of two or more people, to stroke and fondle one another amorously.
- To treat as a pet; to fondle; to indulge.
- To be a pet.
- To be peevish; to sulk.
- A fit of petulance, a sulk, arising from the impression that one has been offended or slighted.
- A term of endearment usually applied to women and children.
- A formal, written request made to an official person or organized body, often containing many signatures.
- A compilation of signatures built in order to exert moral authority in support of a specific cause.
- A formal written request for judicial action.
- A prayer; a supplication; an entreaty.