Present tense in narrative

Hi. In a narrative setting where past tenses are primarily used, do you perceive this kind of sentences being correct (in term of the tense)? I happen to think this type of present tense use is somewhat common in writing but I am not totally sure whether it is correct or not. (I am not sure I wrote correctly to reflect what I wanted to say, though.)

"Boo" to him. Because that is when I got the good idea of helping him with my own money.