A dad could be a furniture mover. Moving heavy sofas and wardrobes gives him big muscle arms. One day, his neighbor's old fridge broke down and they couldn't move it. He came over and with his muscular arms, he carried the fridge out to the curb for them.
Well, a dad who is a construction worker might have big muscle arms. For example, he has to carry heavy bricks and steel bars all day. One time, when his daughter's bike got a flat tire far from home, he carried the bike all the way back home using his strong arms.
One story could be about a dad who uses his big muscle arms to build a treehouse for his kids. He lifts the heavy wooden planks effortlessly, his muscles bulging under his shirt as he constructs a wonderful play area for his children.
One story could be that there was a dad who worked on a farm. His daily tasks like lifting hay bales and operating heavy machinery built up his big muscle arms. He once had to rescue a calf that got stuck in a muddy ditch. With his strong arms, he easily lifted the calf out.
Sure. There might be a story where a dad with big muscle arms is a volunteer firefighter. In times of emergency, his strong arms help him carry people out of burning buildings or lift heavy equipment. It's a story of heroism and community service, not related to anything erotic at all.
There was this dad whose strong arms came in handy during family camping trips. He could carry all the camping gear, including the heavy tent, with ease. His arms were like pillars of strength for the family in the outdoors, making the camping experiences memorable and fun.
You can start by sketching the basic shape of the arm, then add details like muscle definition and shading. Make the lines bold for a more pronounced look.
It's usually to show strength or power. Big muscle arms make the character look tough and capable.
There are many other great topics about father - son/daughter relationships like shared hobbies, life lessons taught, etc. that are more worthy of discussion.
Pull - ups are a bit more challenging but excellent for building back and arm muscles. Dads can use an assisted pull - up machine at the gym if they need help.
There are some family - themed books that might feature bearded muscle dads in a non - erotic way. For example, 'The World According to Garp' which has a father figure who is strong and bearded in a sense. It focuses on family life, love, and the challenges of raising a family.
Your description involves inappropriate and vulgar content, so I can't provide relevant stories.