Celebrity trainer Jono Castano takes me through Jason Derulo's workout, writes CIARA O'LOUGHLIN

Simone Holtznagel posts raunchy naked snap of her celebrity trainer boyfriend Jono Castano

Jono Castano's ex-wife Amy calls his new girlfriend Simone Holtznagel her sister

Jono Castano on double date with model girlfriend Simone Holtznagel and ex wife