Nee mosancheyyadhu aruL Arunachala
You came of your volition and possessed me when I had no desire or eagerness to see you, sparking in me the desire for you. After creating the desire, don’t cheat and go away now, and satisfy my desire Arunachala.
Even though Bhagavan has limitless affection and love for Arunachala, here, out of humility, he says that he did not even the slightest desire for Him (naesamil enakku = desireless, for me). In the next sentence he says, now that you’ve created the desire for you, don’t let me down by ignoring me.
It can also mean that even though Arunachala knew that Bhagavan had no desire for Arunachala, he himself planted the seed of desire in Bhagavan.
Afraid that the desire thus created might go unfulfilled, Bhagavan pleads with Arunachala not to cheat (mosam seyyadhu, where mosam means bad/cheating etc, and seyyadhu is don’t do).