Linky's Fics!

Title: Loyal Guard Dog
Fandom: Kamen Rider Zeztz
Pairing/Characters: Zero/Five
Rating: E
Word Count: 1201
Content Notes: Relationship Study, Character Study, Blow Jobs, Mild Dubcon, Loyalty, Older Man/Younger Man, Adoptive Incest
Author's Note: Written for the Father's Day Incest Flash Exchange. Originally posted on 6/21/26.
Summary: It’s a typical day at CODE. Well, as typical as it could be.

It’s a typical day at CODE. Well, as typical as it could be. Normalcy isn’t an option provided for agents, especially for its commander. Though Zero had no regrets about this.

Combat training is going swimmingly as Five continues to show his prowess on the battlefield. His brutish strength combined with a fierce, unyielding loyalty leads to the decoys being ground into bits. Not to mention his time has been improving. These results are promising.

Zero types notes in his chair, documenting Five’s progress. “Well done.” He says simply. It’s the most basic of praise, but there’s a light that beams in Five’s eyes regardless.

“Only the best for you and for CODE, Commander.” Five smiles widely and is baring his teeth. “After everything you’ve done for me, I need to give it my all!”

He looks up at the young agent, who has grown so much over these many years. Zero still remembers when his father was killed. How the path of CODE was the only option left for him.

After witnessing a nightmare commit such an act—there was no way Five could be able to live a “normal” life. More agents were always a good thing too… His rage against the nightmares could prove quite useful.

Five gave up his name without hesitation. In that moment he threw everything else away, and turned himself into a servant of the organization. Now he was nothing more than CODE’s loyal dog. One that was ready to bite, maim, kill.

Someone who’d express such a mindset always intrigued Zero. He’d make sure to keep an eye on this one. Would his loyalty only grow stronger with time? Or would it wain, as battle scars and trauma continued to pile up?

Thankfully, it proved to be the former. Though to such intense degrees Zero could have never foreseen. If anything, Five had proved to be the most steadfast of all the agents.

An alert pops up onto the nearby screen, a nightmare is on the loose.

Enough musing. It was time to move out.

Lord Invoker in hand, Zero opted to join Five on the battlefield. This was far from his first time doing so. Other times the Zerorider would tag along in his stead. Since the robot is also built for combat.

But Zero wanted to see the recent fruits of his agent’s labor with his own two eyes. All of the recent effort shown in his training… Zero wanted to see his loyal dog go for the kill in person. It would be more satisfying this way.

The pair transformed. Leaping forward at the nightmare, who clearly had his guard down and wasn’t prepared for two foes.

Even as he continued to age, Zero was still extremely sharp in fights. Someone who one shouldn’t underestimate. For it could prove deadly.

Perhaps to impress his Commander, Five especially took the initiative today. Zero would follow along, observing. Letting Five lead the charge. Get in the first hits. Yell out commands. And put in the finishing blow. Pummeling the nightmare into the ground.

Each of Five’s attacks showed no mercy. Zero felt a rush witnessing him fight a nightmare like this. All of his efforts had been more than worth it.

“I am CODE’s guard dog—!” Five screamed with all his might, letting the monster in front of him know who he served. Right before he laid the killing blow.

Five looked to Zero as he towered over the nightmare’s body. While his face was covered by the helmet, he could imagine the expression clearly as if his face was uncovered.

Waiting for approval, praise. Acknowledgment of his effort.

To know he was doing good as the guard dog of CODE.

And CODE had found its loyal dog after all. One that Zero had raised over countless years. After taking him under his wing, Zero created only the finest of agents in the end.

He would definitely make sure this wouldn’t go unnoticed. Good results deserve rewards that were just as high quality.

The break room was near silent. Only the ragged breaths of both men filled the air as Five was tending to his own wounds. Same with Zero.

As Zero applied his final bandage, he silently eyed Five’s body as he stripped down. His physique was on full display in front of him. A beautiful set of muscular arms. A chest and back that was just as lovely. Various muscles lightly bulged around where he’d wrap each bandage. Such wonderful eyecandy.

Time for another daily occurrence between the two: the reward.

He walked over and placed a gloved hand on Five’s cheek. “You’ve done so well for me today.” Zero cooed. Grinning as five obediently leaned into his touch. Letting out a soft breath while his body relaxed.

A quick unzip of Zero’s pants, and Five immediately went down to his knees. Zero is quietly pleased at this showcase of following directions precisely as instructed. Five had become decently skilled in regards to these encounters too. At first he was messy and lacked any experience. Zero had to admit, it was charming.

Over the years Five had learned everything Zero enjoyed behind closed doors, and gradually knew how to push his buttons just right. Plus there was something so thrilling about a man whose obedience showed no bounds while sucking you off. Nothing else out there was quite like it.

Loyalty in both the battlefield, and the bedroom was always a lovely combination.

Licking from base to tip, it didn’t take long for Five to take in all of Zero. Getting to work. Just as usual after any successful mission.

Zero grabs his hair and shoves his dick in even deeper. And Five takes it like the agent he is.

“Good, good… Exactly like I taught you.”

“Mm.” Five begins to moan softly as Zero fucks his mouth.

The extra stimulation from his moans feels so good, and it doesn’t take much longer after that to come in his mouth. Zero finds he was extra worked up today. Ogling the younger man’s body certainly didn’t help there when it came to his stamina.

Zero strokes Five’s head, not unlike a master petting his dog for a job well done.

Five looks up to his commander with absolute reverence. Leaning into the gentle touch with a tiny smile, that light in his eyes is present again. His allegiance is on full display, and no questions as to who he served were left unanswered.

Zero had a hunch he was the only one who'd get to see him like this: Genuinely smiling, possessing a brightness in his eyes. The rest of CODE would witness his rougher side, though both halves of Five contained his loyalty to Zero and the organization all the same.

He knew this was the man who raised him into a fine agent. Made him strong. Gave him a home when everything he knew was taken away. Taught him to fight against the nightmares. Fought by his side again and again. Hardened him into a strong agent, a soldier for this cause.

Zero was the man who made him into CODE’s guard dog—and Five thanked him for it.