你存在我大姨的脑海里
[nĭ cún zài wŏ dà yí de năo hăi lĭ]
This name, humorously or poetically, suggests that the person represented by 'you' only exists in the memory of a relative, specifically an aunt. It could be used to express some sort of estrangement, where a distant relationship only remains as recollection.