Final answer:
The character's remark is an example of irony, specifically verbal irony, wherein the character's attempt to appear humble inadvertently reveals a trace of vanity.
Step-by-step explanation:
The remark made by the character is intended to be humble and self-effacing, likely to avoid any accusation of self-aggrandizement. However, the mention of not wanting to repeat 'many gracious expressions' due to a fear of being seen as vain actually reveals a certain degree of vanity in itself. The irony here is that in attempting to be modest, the character actually draws attention to their own virtues. This technique is commonly used in literature and is often referred to as irony or a specific type of it, which is verbal irony. The use of irony in literature serves to engage the reader and prompt them to consider the underlying meanings of what is being expressed by the characters.