It most certainly isn't in line with his character no!!
The Nazirs were brought into the show on the pretext of being a devout Muslim family whose religion mattered to them!!
Sharif was far less than happy when Kal took up with Leanne because of her past & even less so when they decided to live with each other outside marriage and he practically disowned Alya after she had her one night stand with Jason (which incidentally came whilst she was dating Gary & making him wait until they were married before having sex!!)
Not only that but the guy was portrayed as completely happy in his marriage to Yasmeen, mildly amused by her ovrrbearing personality, happy just to sit outside with his hens for relaxation!!
Now we are supposed to believe he's been carrying on this horrible sleazy affair outside of his marriage for the last seven bloody years & now just to add to the family sleaze
What next ffs, the sudden revelation that Yasmeen's actually a lesbian whose about to be Sophie's next partner??