Explanation:

- At least six people buy after H, so H is at position 2 or earlier.

- Two people buy between H and C.

- M is after F and before E.

- C and E have no more than two people between them.

- A is after H and before G.

- G is not last, and has less than three people between G and B.

- B buys before G but is not first.

Let's determine the sequence:

1. H is likely 1 or 2 as six after condition.

2. C is either Position 4 or 5 considering spacing and other constraints.

3. M sits between F and E; we deduce F is early in sequence.

4. A is before G but after H.

5. B can't be first and is before G.

Considering these constraints:

- F-M-E aligns after H for M's placement.

- B can be before H or between.

- Relatively place A before G and evaluate.

On evaluating options:

1. FA: F buys Book directly before M; makes sense.

2. BG: B buys before G; valid.

3. AE: A is before G; does not specifically go before E or M.

4. GM: G is later, M's after F/E.

5. AK: No prior positioning relevance.

The odd one out is AE, since A has placed relevance before G, not E.

AE is the correct odd one out.