Hey rushi ... Actually, krishna-draupadi friendship happened after her wedding to the pandavas.There are mentions of a private quarter which could only be used by arjuna/krishna/draupadi and sometimes the first two wives of krishna.Sanjay is describing the scene to dhritrashra and says "krishna sat on the bed with his feet on arjunas lap while arjuna had his legs in the laps of draupadi".Draupadi and krishn together used to make fun of the poor arjuna while arjuna complained and made fun of her to krishna