Chuckling about Malfoy, they waited, Norbert thrashing about in his crate. About ten minutes later, four broomsticks came swooping down out of the darkness. Charlie's friends were a cheery lot. They showed Harry and Hermione the harness they'd rigged up, so they could suspend Norbert between them.
-Harry potter and the sorcerer's stone (J.K Rowling)
'Cheery' means happy and cheerful, but what does it mean by 'they were a cheery lot'? Is it saying
(A) Charlie's friends were very (= a lot) cheery?
(B) Charlie's friends were a lot of people, and they were all cheery?
For me neither of these seems right because I think 'a' and 'lot' cannot be written separately since 'a lot' as a whole means 'very or very much'. And also it looks weird to put an adjective 'cheery' between 'a' and 'lot'.