what might have been Enn's first indication that something was amiss with the girls ath the party? Did he seem to recognize the strangeness of their dislogue?

Enn's first inclination that something was amiss with the girls at the party would have been the bizareness of the name of the first girl Wain's Wain, the second girl with a gape-tooth that claims she has been to the Sun and the third girl Triolet who puts him in a trance after she whispers a "poem" into his ears.

Explanation:

In the short story "How to Talk to Girls at Parties" by Neil Gaiman, a shy boy Enn goes to a party with his extrovert friend Vic.

When they arrive at the party, Vic meets a girl named Stella and starts flirting with her and encourages Enn to flirt with any girl of his choice.

Enn begins talking to a girl named Wain's Wain who somehow sees herself as a "second" because of a deformity on her finger, she goes on to tell him a very unusual story about being in Rio and says she is not "permitted" to participate in much and she is gone when Enn leaves to get a glass of water.

He meets a second girl with gape-tooth that claims she is a tourist who has been to the Sun. Vic interrupts them and says they are at the wrong party because a lot of weird things were happening and the girls might be aliens.

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