"That's okay, Daizo" Luke said, "but maybe there's something I can do for you."
"What do you mean?" Daizo asked.
"Do you still have that childhood dream of becoming a sumo wrestler?"
Daizo blush turned redder, "oh, Ryuji, I gave that up when I was just a boy. It is far too late now. I would have had to start training in a stable at a young age to be anywhere close to proper physical condition."
"Forget about that. If I said you could live out the fantasy, would you trust me?" Luke/Ryuji held out his hand.
Daizo nodded and grabbed Luke's hand, "I trust you."
"Then let's go back" Luke led Daizo back to the Inokawa family's sumo shrine. He knew what he was about to do was risky, but he couldn't help but feel sympathy for Daizo. The kind man had such regrets, surely he deserved to be happy. "I want you to close your eyes until I tell you to open them." Daizo nodded in response. Luke grabbed the Inokawa ancestor's mawashi from the wall and brought it to Daizo. "Lift your right leg, now the left" Luke instructed as he guided the mawashi up to Daizo's waist. Luke had to hold it up as it was much too large for Daizo. Luke considered Daizo to strip, but decided it was too awkward to ask a man he just met to get naked. His current clothes would have to be a casualty of the transformation. Finally, Luke placed the magic amulet around Daizo's neck.
Luke wasn't sure if the amulet was working, until Daizo said "Ryuji, I don't feel well" followed by a belch. "Excuse me! I don't know what came over me" Daizo bowed, causing him to rip an embarrassing fart. Luke chuckled knowing Daizo must have been experiencing the same bloated feeling that came with the sumo transformations.
"You can open your eyes now" Luke said, and Daizo did as he was told. He saw the more than 600 pound sumo hunching down beside him. He looked down to see Luke was holding up the comically large mawashi around his waist.
"Is this my ancestor's mawashi?" Daizo asked, "so that's what you meant by living out the fantasy. It would be a fun idea if it fit on me." Still looking down, that's when Daizo noticed a bit of his waist obscured by his suit shirt. He attempted to tuck it back down, but it was his stomach that was pushing it forward. Daizo patted his gut, feeling the extra pounds where he thought he had perfect abs. "Have I let myself go" he thought. Certainly most men at his age juggling a career and a child would gain some weight, but Daizo thought he was an exception. Apparently not, as he felt a sudden tightness around his ball gut. "I guess I've been cooking myself. I can't wear the same size I did in my 20s" Daizo thought. In fact, he was feeling that tightness everywhere in his suit now. Luke could see how Daizo's body went from that of a samurai to a sedentary office worker past his prime, then to a man who looked like had been fat all his life and continued to get bigger. His nipples were bleeding through his shirt because of how much his fattened pecs were pushing against the breast of his shirt. The shirt that was also rising above his belly button as Daizo's stomach became too large to contain. The changes were too obvious now. Daixo placed his hands on his face, feeling the plump cheeks on his round face. Luke could tell that Daizo was trying to keep his composure, but it was obvious the man was disturbed.
Strangely the transformation slowed down once there was no more room left in Daizo's suit for him to grow. He was still far from being large enough to fit the mawashi. That changed once they both heard a rip. Daizo's ample rear made a tear in the seat of his slacks which spread to the crotch, Allowing his freed ass to bubble out. This was followed by his hips and thighs, leaving shreds of the slacks and boxers falling down to be replaced by the now fitting sumo apparel. The buttons of his shirt popped off as his torso grew in all directions, but especially the sides and front. The force of Daizos bolder of a stomach impacting with Luke was enough to make Luke fall down. The suit shirt wasn't shredded like the rest of Daizo's clothes, but it was struggling to cling to his fattened arms.
Looking up at at Daizo's new form, Luke saw that he wasn't fully transformed into the Inokawa ancestor. He had the silhouette of the over 500 pound sumo, but his skin tone and facial features were clearly Daizo's. He even still had his koi fish tattoo. Instead of donning a sumo chonmage, the top hairs of his business cut grew longer and were tied back in a bun. Luke wondered why Daizo didn't fully change and realized he still had his suit shirt clinging to his arms. Maybe because Daizo was wearing two articles of clothing owned by two different people, he became a split between himself and the Inokawa ancestor.
"What... What happened to me!?" Daizo yelled, "I... so fat... this isn't me!"
"Woah, relax" Luke removed the amulet and tugged the suit shirt off of Daizo. "I told you I would help you live out your sumo fantasy."
"No, that's impossible. People don't just change like this. I have a career! Responsibilities! I can't work like this."
"That boring desk job was holding you back" Luke cupped Daizo's face. "You said the reason you aren't a sumo is because it was too late to train your body to sumo form. Now you have the body of a sumo!"
"I... I..." Daizo stammered.
"Fight me."
"...what?"
"Fight me" Luke smirked, "we're both sumo now. If you truly respect sumo as you say, you will give me a challenge. Daizo pondered this request for a moment, and finally gave a determined nod in acceptance. Luckily the Inokawa sumo shrine already had a sumo ring design on the floor. They stood behind two white lines at the center where Daizo spread his legs to take large "sumo stomps". Luke mimicked this, not knowing the traditions himself.
With no gyōji around, Daizo took it upon himself to shout the calls. "Jikan desu, te wo tsuite." They both leaned forward and placed their hands on the ground. "Hakki-yoi!" Daizo charged forward first. Despite being caught off guard, Luke utilized his greater weight and placed a foot behind him to regain stability. Still, Daizo kept the pressure on by using open hand hits to push Luke back. It seemed Daizo had the better technique, being more familiar with sumo wrestling as a sport. Luke grabbed Daizo's mawashi in an attempt to take advantage. He tried to throw Daizo down, but the smaller sumo held his ground. Still, Daizo couldn't resist Luke's strength pushing him down quite a bit, and in the process Daizo's face came plummeting into Luke's cleavage.
"Hey! That tickles!" Luke cried while his body shaked in laughter. This shaking caused Luke to get involuntarily motorboated, since his swinging man boobs pushed Daizo's face side to side. All of this excitement made Luke's dick throb, which was already hard inside his tight mawashi. It got more intense when Daizo grabbed the front of Luke's mawashi and accidentally fondled Luke's crotch.
Luke moaned and thrust his hips forward, his stomach pushing Daizo off balance, making Daizo collide with the floor. Luckily Daizo's weight cushioned the fall, but it also left him in a curious position. Face down laying on his belly, facing away from Luke, Legs spread apart, and with his ass up in the air like two hilltops. Luke's thrust threw his own heavy belly too far forward for him to maintain his center of balance and he too came falling down on to of Daizo, his stomach resting on the curve of Daizo's back.
"Oof! This is no good. Let's get back up" Daizo suggested while he struggled against Luke's weight. All Luke could focus on was how Daizo's thick ass kept pushing against his cock.
"Oh Daizo, keep going" Luke cooed and began dry humping between Daizo's cheeks.
"R-Ryuji? What are you doing?" Daizo blushed.