Meaning:
"自来" means "innate," and "旧" means "worn out" or "old." Originally used to describe things with a retro vibe, this term has been jokingly used to refer to people who look much older than their age. People often use it on themselves or someone they are really close to. Others may feel offended if you use the term on them.
Example
A: 昨天和你在餐厅吃饭的是你男票吗？他是不是比你大很多啊？
Zuótiān hé nǐ zài cāntīng chīfàn de shì nǐ nánpiào ma? Tā shìbùshì bǐ nǐ dà hěnduō a?
Is that your boyfriend who was having dinner at the canteen with you yesterday? Is he much older than you?
B: 其实他和我同年的，不过有点自来旧。
Qíshí tā hé wǒ tóngnián de, bùguò yǒudiǎn zìláijìu。
Actually he is my age, only he looks much older than his age.
(Edited by Stephanie Yang)