sonic and highschool DXD romance

Chapter 9: Sonic first summer break with Rias and the gang.

After a couple of weeks sonic was able to get back the rest of his transformations and Rias was being more lovely towards sonic as was everyone else expect Issei and Kiba but treated like a brother, sonic was with the gang relaxing "alright everyone it's the summer break and we're taking a trip down to the underworld" Rias said everyone was excited but Rias realist that sonic had never been to underworld before and fill him in soon sonic understood and was a little nervous but it meant more time with his friends and most importantly more time with Rias because sonic realised that he had feelings for Rias and love her not because his devil side told him but because he actually felt that there was something more than friendship, on the train to the underworld (yes, you read right there is a train to the underworld) on the way their everyone was shocked to see Koneko was sleeping on sonic's lap making sonic blush but got used to it he puts on his earphones and listen to some music 

hours passed by sonic was relaxing so much that he didn't realised that Akeno, Xenovia and Rias was resting their head on sonic as well while sleeping until someone on the train hit the emergency stop and caused everyone wake and the girls noticed saw they were on top sonic, who woke up and felt the four girls body's pressing agianst his body when everyone got up and saw Azazel

walk in and told them that someone made the train he and Rias went out for a chat.

When they left everyone fell through the floor and had a rough landing but sonic was smart to use his energy to fly down but got smacked down because everyone saw a purple dragon

and it didn't look friendly but before anyone could do anything it attacked sonic but he was fast enough to dodge it "okay big guy you wanna fight bring it on!" Sonic used kaioken and charged at the dragon but smack down but what the dragon didn't expect Sonic to turn super sonic blue Kaiokenx20

and upcut his chin forcing him back in pain. Sonic didn't stop there he kept up the assault on the Dragon making groan in pain but unfortunately since sonic couldn't get much training in blue Kaiokenx20 was still painful sonic stop to take a breath then the dragon attack but was stopped by Akeno shooting lighting and the others attack except Asia who was helping keep the stress of the Kaiokenx20 from killing sonic. But this only angered Sonic, feeling that he wasn't strong enough to fight and everyone to fight for him but most importantly he felt like his promise to the shadow was gone.

(flashback)

Sonic was in the judgement hall waiting for Amy rose to come and start the loop again but then shadow appeared in front of him "huh shadow what's wrong?" Sonic asked "sonic if I die and you kill Amy for good then I want you to keep something of mine" Shadow said "what's that?" Sonic replied "....sonic please I want you to keep my pride within you" shadow said "alright shadow I promise to carry your pride within me thank old pal now let's give this megalomaniac a bad time" sonic said and shadow walked away with a smile.

(end of flashback)

Sonic felt the fire within burn even more and wanted to keep his promise to his friend to carry his pride he stood up ignoring the pain that the Kaioken was giving him and Asia telling him to stay still he charged at the dragon but smacked down by it's tail "sonic you've done enough damage we can take it from here" Akeno said "yeah besides if that's the best you got your at your limit of helping out so just-" "LIMIT. WHAT FUCK DO YOU ABOUT MY LIMIT!!!!!" Sonic shouted while standing up "I'M NOT DOING THIS FOR FUN, I'M DOING FOR THE PRIDE OF MY FRIEND!" Sonic said and his quills started to glow "I HAVE TO KEEP MY PROMISE AND I WILL BREAK FREE OF ALL MY LIMITS AND AS FOR THAT DRAGON, I'M GONNA MAKE SURE HE BURNS IN HELL!!!" Sonic said and his super blue form change he went beyond it normal limit's his aura was dark blue and so was his eye's and quills "this is everything I have and beyond, dragon" sonic said as he walked towards the dragon everyone was in awe while Akeno, Xenovia and Koneko was red faced because they found sonic x100 more handsome to them and then sonic rushed at the dragon an overpowered it easily until the dragon powered up to full power and sonic still overpowered it but was still new to the form so he was losing more stamina than the blue kaioken "alright time to finish this" sonic land on the ground and powered up to the max "say hello to my friends most powerful attack. FINAL FLASH!"

(Sonic is Vegeta and the Dragon is Jiren)

Sonic shot the blast and it's target dead-on but when the smoke cleared the dragon was still there but badly wounded but unfortunately sonic lost this new form, from lack of power and stamina.

Everyone came to sonic to help and the dragon was about to shoot a fire until "that's enough" the dragon stop and everyone saw Azazel and Rias come after they explain that this was a test to see how powerful everyone had gotten but was surprised about sonic taking his blue form to a new level and after told sonic that the purple dragon was called Tannin who chose to be a devil dragon "sorry for not telling you guys but I wanted to see how much more powerful we gotten" Rias explained then she saw that sonic was covered in wounds, dirt and looked really tired then she saw everyone else was the same "well we can't see my parents all dirty like that so let's get cleaned up" Rias said later on everyone was in a special bath area despite the girls begging sonic to join them sonic chose he hangout with the guys after everyone was cleaned up went to bed to continue the train ride the Gremory mansion, sonic was lucky he got sleep without the girls so he could getting a break from the girls.