This is another muscle growth series I've made, this year of 2021 features a dragon TF theme, similar to my Pokemorph episodes but a third form is a giant feral dragon. Additionally, humans and anthros, as well as characters from shows or movies, coexist in this new universe.

Foremost to see the first target to start this series, with elements related to Bakugan, requested by  MuscleVonMon. Enjoy

Summary:
Several months after sailing off to another adventure, Dan Kuso returned home, only for his friends to surprise him with a reunion party, much to his joy. However on the next day, he received a letter with unknown sources from a mailbox, which read that his skills were much more needed for the outside world. Although confused and skeptical, he decided to go, along with his friends' support, to the city airport to meet a female English agent, who gave him the details on his next mission. He was sent to the United Kingdom to investigate the Stonehenge where something strange had happened few days ago.

Part 1
Dan Kuso had arrived at the Stonehenge, that hadn't appeared as normal as before.

Dan Kuso: Hey Shun, Agent's right about this strange phenomenon here in the Stonehenge. The standing stones are carved with glowing runes and the rock in the center has some burned marking that resembles some sort of a gear.
Dan Kuso: Yeah, I'm sending these pics to you right now.
Unseen woman: No need to, young man.
Dan Kuso: Wait a sec, who said that?
Unseen woman: I am a magical guardian of the ancient creatures who used to be feared by many across Medieval Europe.
Dan Kuso: Then why don't you show yourself?
Unseen woman: I do not need to, my young warrior.

Part 2
Someone hiding behind the stones had not only transformed Dan Kuso into a muscular dragon, technically a dragonoid with humanoid elements, but she also had corrupted him entirely. It took minutes for Dan to transform magically, because it also had to alter his personality. All of his good, if not all heroic, traits were replaced with a mindset of both a willing servant and an authoritarian soldier: serving his new unknown master with all his might. Yes, unfortunately some wizard had forcefully turned Dan into someone beyond recognition of his friends.

Unseen woman: Hmm, so hot, are you not? Do dragons deserve to be feared by all?
Dan Kuso: Yes, my Queen. Not just in Europe.
Unseen woman: Ooh, I've hit you beyond that. So, why is that?
Dan Kuso: Thanks to your presence, we will turn any sentient being in the world into powerful dragons, serving nothing but you, my Queen.
Unseen woman: Excellent my young warrior. Now first things first, get rid of that evidence you are holding.
*Dan Kuso effortlessly crushes the electronic device with a smug smile.
Dan Kuso: Done and done. Can I start my first mission?
Unseen woman: Yes, oh how I love your eagerness, but you can not go out just in that form alone. Allow me to give you powers.

Part 3
Dan's willingness to turn against even his own friends showed how powerfully capable was his new master of. She also had another thing in mind, she had also given him a second form he could transform to or revert from: Dragon. Yes, a literal feral one, but bigger and more dangerous.

Dan Kuso: Wow! This is awesome! Way better than being a weak, pathetic human!
Unseen woman: Your friends will soon love it. Why don't you invite them one by one here? Feel free to watch the show, because the rest is up to me. Now hide.

Conclusion:
In conclusion, Dan Kuso had become the very first victim to become a member of a draconic and dominant species bent on world domination and turning everyone into dragons. And it all started in the Stonehenge, but I can't blame Dan for falling for it, as you've already heard, there must be someone else who needed a bait in playing the bigger picture.

Now I'm not into diaries more often, frankly because I used to be an agent. Yes, I was Agent 22 at the time. However, if you can't recognize me, perhaps you will know my name. My name is Bentina Beakley, once serving the richest duck in the world, now a 'female English agent' serving the secret organization looking ways to prevent a malevolent kind of dragons, that seeks nothing but conquer the world and turn everyone into loyal, muscular dragons. This reminds me a bit of Darkseid and his Parademons, isn't it? Does it? Maybe so, but nevermind, Agent 22, out.
--Bentina Beakley, formerly nicknamed Agent 22

Dan Kuso owned by Bakugan
Bentina Beakley (by description only) owned by DuckTales (under Disney)

Celtic Origins 2021:
Dan Kuso + Undie + NSFW || Runo Misaki + Undie + NSFW