Towering over 200 centimeters (6'7"), Hyakuzawa is said to be an extremely imposing figure. He is usually seen wearing a neutral expression until he gets fired up while playing volleyball. Hyakuzawa has short, black hair in a partial buzz cut near the bottom half of his scalp.
In contrast to his domineering height, he is very soft-spoken. He also seems to be a serious and subdued person, which can be seen from his respectful demeanor to his seniors. He doesn't react much other than an simple acknowledgement that he's listening even when his seniors openly praise and brag about him being an asset to the team. Before his match with Karasuno, Hyakuzawa mistakenly believed that his natural height and power was enough to beat Karasuno, thinking Volleyball was simple. Later when Hinata proves him wrong, Hyakuzawa takes the initiative to seek out his senior to recant his words after being humbled.
Hyakuzawa also appears to have a strong sense of responsibility. He is aware of his own limitations and lack of skills, and it's due to this that he doesn't want to be a burden to his team. He is willing to do everything in his power to contribute. 
Hyakuzawa is relatively new to volleyball. By the time of the Miyagi Prefecture's First Spring High Preliminary, he has only been playing volleyball for a half year.
Spring High Preliminary ArcEdit
Hyakuzawa and his team, Kakugawa, face off against Karasuno in the second match of the First Spring High Preliminary. When he walks past Karasuno, his presence alone is intimidating enough to fluster his opponents, especially Hinata. Kakugawa is fully intending on using Hyakuzawa's overwhelming height as an ultimate weapon. So his seniors instruct him to focus on spiking and taking points from Karasuno.
The minute the match starts, Hyakuzawa spikes over three blockers to score for the first point of the match. Later when Hinata attempts a feint, he easily stops it and pushes it back down toward Karasuno's side. Hyakuzawa continues to dominate at the battle near the net, pushing Kakugawa's score to 3-0. Karasuno is eventually forced to call a time-out as they failed to deal with Hyakuzawa. During the time out, Hyakuzawa listens to his seniors discuss their plan of keeping the ball in play so they can make the best use of him. He then looks back at Hinata and admits that he feels bad for Hinata since Hinata's jumping with so much effort and yet is unable to do much. One of his teammate assures Hyakuzawa that his height is the ultimate advantage. In response, Hyakuzawa reveals his opinion on volleybally being pretty simple.
Once the match resumes, Hyakuzawa finds his spikes being received after Karasuno purposely adjusted their receive formation. Later, he tries to read block but is taken completely by surprise by Karasuno's minus-tempo quick. Hyakuzawa soon realizes just how wrong he is when Hinata continues to spike before Hyakuzawa can even reach to block. When Karasuno takes the first set, Hyakuzawa shows no sign of being discouraged. He is determined more than ever to take back points for his team. His intensity continues to grow even when Karasuno is at match point. He goes on the offense and is surprised to find Karasuno using a soft block to hinder his spike. For the last point, he faces Hinata in a head-to-head battle. Hyakuzawa is certain that he would win now that Hinata can't use his speed to his advantage. However, he is once again proven wrong when Hinata hits a block out targeting his fingertips, winning the match in the process. Afterwards, Hyakuzawa calls out to his teammate to take back what he said about volleyball being simple.
Tokyo Nationals ArcEdit
Hyakuzawa is one of the first year players selected to attend the Miyagi First Year Intensive Training Camp. As part of training, the players are playing 2-on-2 matches. Hyakuzawa, being the most inexperienced of the bunch, quickly finds himself lagging behind the others. The other players have compared his skills to that of middle school level and dreaded being paired with him. As he grows more insecure and depressed, he accidentally blurts out to Hinata that he should have been the one invited to the camp instead. Hyakuzawa quickly realizes his mistake and mentally berates himself for saying such careless words. Hinata doesn't take any offense. Instead, Hinata assures Hyakuzawa that he deserves being here for having the "ultimate talent" that is his two meter height. 
After further encouragement, Hyakuzawa is seemingly inspired by Hinata's words and agrees to test something out for Hinata when asked. He takes Hinata's suggestion of his gameplay to heart and uses it in the next 2-on-2 match. When the pace becomes increasingly fast, Hyakuzawa lands a first touch that returns the ball high, buying his team enough time to regroup. Once they did so, Hyakuzawa spikes the ball above Kunimi's block. Afterwards, Hyakuzawa shares a high-five with Hinata, signifying a developing camaraderie between the two.
For the rest of the training camp, Hyakuzawa is performing a lot better and beginning to find his own rhythm to keep up with the rest.
Hyakuzawa is very new to volleyball and can barely understand the rules. Although he has height, his lack of technique means he can only score points through spikes and return serves. So far, he is only shown to be able to spike crosses.
Jumping Reach: 347 cm
Komaki is Hyakuzawa's senior and the captain of the team. Hyakuzawa is very respectful toward Komaki and follows his instructions without any complaints. When Komaki seems to be shaken by Karasuno's strength, Hyakuzawa assures him that he will do whatever he can to take points back.
Yūdai respects Hinata and sees him as a rival. He acknowledges Hinata's ability when he was training with the area's best first years. In fact, Hyakuzawa thinks that Hinata should have been the one invited to the training camp and not him. Hyakuzawa sparks a friendship and even deeper rivalry with him when Hinata gives him advice and words of encouragement to improve his gameplay. When asked why Hinata helped him, he feels that spark when Hinata explains that he wanted to take Hyakuzawa down at his very best.
- Favorite Food: Yakisoba
- Current Concern: Receives are difficult.
- His star sign is Aries.
- He shares his birthday with Watari (3rd April)
- "You know, passing is hard and all, but volleyball is...pretty simple." (To his teammates, Chapter 103)