Collar and Cuffs

Collar with integrated cuffs. Arms up, palms placed on back, touching below the neck. Reverse fiddle.

Here are a couple of options for customization (because sizing - you could just scale, but the bolts will be different). Wrist to neck ratios will also vary. Example uses the 40mm bolts from eSun filament spool. The "slim" version uses a 2.5-3mm diameter nail and a 6mm diameter magnet to snap it in place (have fun).

Compile in OpenSCAD using Customizer for fit (about 25 minutes).

I might be inclined to take custom requests if you message me your measurements (and post a make!). Neck circumference for a firm fitting tape (some give is already built-in). Wrist diameters at the widest and narrowest width.

Featured model: https://www.cgtrader.com/products/free-realistic-female-korean

Sample parameters used (cuffs.json - OpenSCAD presets; won't upload due to file type restrictions)
{"parameterSets":{"slim":{"$fn":"24","bolt":"3","cuffs":"48","cuff_angle":"0","head":"4.5","headh":"3","height":"30","hinge_angle":"0","neck":"390","necks":"96","nut":"6.2","nuth":"3","nuts":"24","padding":"8","recess":"1.6","rounding":"5","tol":"0.4","wall":"3","wrist_angle":"40","wrist_offset":"11","wrist_rotation":"10","wrist_thick":"40","wrist_tilt":"18","wrist_width":"60"},"chunky":{"$fn":"24","bolt":"6.5","cuffs":"48","cuff_angle":"0","head":"9","headh":"5","height":"30","hinge_angle":"0","neck":"390","necks":"96","nut":"12","nuth":"8","nuts":"6","padding":"8","recess":"1.6","rounding":"5","tol":"0.4","wall":"9","wrist_angle":"40","wrist_offset":"11","wrist_rotation":"10","wrist_thick":"40","wrist_tilt":"18","wrist_width":"60"},"closed":{"$fn":"24","bolt":"6.5","cuffs":"48","cuff_angle":"0","head":"9","headh":"5","height":"30","hinge_angle":"137","neck":"390","necks":"96","nut":"12","nuth":"8","nuts":"6","padding":"8","recess":"1.6","rounding":"5","tol":"0.4","wall":"9","wrist_angle":"40","wrist_offset":"20","wrist_rotation":"10","wrist_thick":"40","wrist_tilt":"18","wrist_width":"60"}},"fileFormatVersion":"1"}