~~Show them your titties!
Everybody loves titties man!
Either they will immediately start nibbling on them or they will not react. But then, you would've released the tension in the air.~~
Dear OP,
Flashing them at this stage is NOT a good idea.
Start with holding pinkies while sitting at a table. Then you can proceed to holding two fingers.
Work your way through having their hand in yours.
Let them know that physical touch is endearing and you want to give as well as feel this with them.
Be at an open area and ask them if they would sit close to you. That way it's you who is cornered and not them.
With time, they should get comfortable with you.
Once they are comfortable, THEN you should proceed with the earlier suggestion.