This lora generates the handjob position seen in the showcase images.

Version 2

Main improvement is adding clenched hand and more prominent motion lines for maximum milking ( ͡° ͜ʖ ͡°)

Recommended weight: 0.3

Higher weights can be used, but will likely impact the art style.

Main tags:

tekoki, handjob, small penis, bed, pillow, on back, spread legs, pov, motion lines, clenched hand,

I recommend specifying an action for the second hand as well, such as any of the following:

arm behind head,
pov hand, breast grab, hand on another's arm, guided breast grab,
finger to mouth,
fellatio gesture, open mouth, tongue, saliva,

Optional tags:

ejaculation, cum on stomach, cum on breasts, cum on clothes,
looking at viewer, looking down,

Version 1

Recommended weight: 0.6

Weight can be between 0.3 - 1.0, but the art style might be affected at higher weights, while lower weights don't really work for specifying which hand.

Main tags:

tekoki, handjob, penis, bed, pillow, on back, spread legs, pov,

Additional tags:

right-handed, left-handed, two-handed handjob,
ejaculation, cum on stomach, cum on breasts, cum on clothes,
motion lines,

Pony version: https://civarchive.com/models/830815/handjob-on-back