My male colleague texted me to call my sister. What does he mean?

Male colleagues call you sister, which may have the following meanings:

1. He may really regard you as his sister, for various reasons. For example, he may think you are kind and lovely, or he may just want to care about you.

If he always calls you sister, it may be because he is worried that you will misunderstand his feelings for you. This may be because he already has a girlfriend, or he has no other feelings for you, but he doesn't want you to misunderstand, so he will choose this title to delimit the boundaries between you.

He may also want to get close to you and like you. In this case, he may be full of joy every time he meets you and always want to be close to you.

Please note that these may not be comprehensive, and the exact meaning of his calling your sister may need to be directly asked or considered about his personality and the specific situation at that time.