Raksha Bandhan story in Hindu mythology

Today is  Raksha Bandhan day.

Today a sister will tie a rakhi around the wrist of her brother. 

Brother gives a gift to her saying that he will take care of her. 

This tradition is ongoing from ancient times. 

We know about Vamana and Bali.

King Bali though a demon, he was the ardent follower of God Vishnu.. 

God Vishnu took the form of Vamana and pushed Bali to patala loka. 

But Bali requested God Vishnu to be with him always. 

How can God reject his ardent follower's wish ????

So God Vishnu was staying with Bali as his security guard. 

But there was a chaos created in the universe in the absence of God Vishnu. 

That time, Goddess Lakshmi who  is the wife of God Vishnu , came near Bali disguised as a poor girl .

She tied the  rakhi around the wrist of Bali.

Bali asked her what she want as the gift ?? 

That time Goddess Lakshmi asked for her husband God Vishnu. 

Bali without saying anything, released God Vishnu.