there is no jeeju sali relationship exisitng between Arjun and Purvi.
Arjun and Purvi had sexual relationship before Arjun marrying Ovi. In that case Arjun accepted Purvi as his wife that night he touched her. Society may require external rituals like magalsutra and Sindoor. but truth is Arjun and Purvi are husband and wife when they gave themselves to each other with their whole heart.
Ovi is considered second wife because Arjun had relationship with her too.
Till now Purvi and Onir didn't consumate their marriage. but married.
Arjun- Ovi and Purvi-Onir marriages are legally valid in the eyes of society only. internally there is some other relationship which is deal. both marriages are deal marriages. and there is no PR because Arjun and Purvi had relationship and married another.
i'm not talking about who is at fault here. this is my POV on jeeju Sali relationship between Arjun and Purvi