Jason Grimshaw unknowingly has a drunken romp with his aunt in an upcoming episode of Coronation Street.

The Street’s resident hunky builder, played by Ryan Thomas, is feeling dejected after Becky Granger (Katherine Kelly) refuses his marriage proposal in favour of Steve McDonald (Simon Gregson).

Down in the dumps, Jason is then comforted by his older relative, with devastating results.

Factory supervisor and Jason’s aunt Julie Carp, played by Katy Cavanagh, is also miserable after splitting up with Kirk Sutherland (Andrew Whyment) and succumbs to Jason’s charms, The Sun reports.

But the pair are unaware they are related and all hell breaks loose when the truth comes out.

A show insider said: “They are both horrified when they finally discover the truth.”

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