Padmamalini is one among the numerous names of Goddess Lakshmi. The name is found in the Moksha Dharma Parva of the Shanti Parva of Mahabharat. Goddess Lakshmi narrates her story to Indra in the chapter of Mahabharata.
Padmamalini because she emerged from lotus which was fully bloomed by the rays of the sun. The name also means one who wears garland made of lotuses.
It is believed that initially Padmamalini resided among daityas or demons as they then had clean habits and good moral behavior. But when all forms of corruption set in the daitya society she abandoned them.