Final answer:
Paul believes the 'little brunette' is more interested in him when he is quiet and reserved, highlighting the irony in what he perceives as appealing.
Step-by-step explanation:
Ironically, Paul thinks the 'little brunette' is more interested in him when he is remaining quiet and reserved. This is contrary to what one might expect since boasting or displaying acts of kindness typically are seen as methods to attract someone's interest. The narrative suggests that by simply being more reserved, he appears to gain the attention of the 'little brunette', highlighting the irony in what actually makes him seem more appealing to her.