Mukkur lakhsmi Narasimacharya writes about this in 'kurai ondrum illai' as follows.
"When lakshmi came out of the occean asuras and devas were stunned by her beauty.All wanted to marry her.But lakshmi gave a condition."I will marry the person who doesnt desire me"
Devas and Asuras couldnt even pretend that they did not desire her.Lakshmi took a garland and moved ahead.She went to vaikunta where the balck thirumeni was laying.She saw him,he saw her.She saw nothing in his face.She only saw mercy and vatsalya.
"Dont you desire me?" she asked.
"Who are you?" asked vishnu.
Immediatly she garlanded vishnu.Since he was girupamoorthy he accepted her immediatly.
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we always see this repeated.In every avathar it is lakshmi who falls in love.Vishnu doesnt fall in love so easily.He never proposes.He only accepts proposals.
In krishnavathar ,Rukmani falls into love on krishna without even seeing him.Her father arranges her marriage with another king and Rukmani writes the first 'love letter' in recorded history to krishna.What was written in that love letter?
"Hey krishna,in yagnas havis will be given to devas.Wont it be ludicrous if a fox comes and snatches away the havis given to Lord vishnu?Similiar will be the case if I marry somebody else.
I am the havis given to you the purusha simman.How can a fox take away what belongs to a lion?take me"
After this love letter krishna comes and takes away Rukmani.
Radha's case is even worse.She first hears the name krishna.She immediatly falls in love with that name.Then she sees a beautiful youngman who grazes cows.She falls in love with him too.Now she is confused.She is in love with two persons.But to complicate things more she hears a venuganam and falls in love with the person who played thye flute.
She cries to a friend of her saying that she is in love with 3 people at the same time.Her friend consoles her by saying all three are the same.Radha is relieved.