'Biology is the study of life.' Mr. Lee explained. 'We should respect all kinds of living organisms. But above all we should respect our own creation.'

His three students were sitting in the grass. Kyu was leaning against Hae, his head on the other's shoulder, trying to lure out the fire handler.

'Please sit straight up, Mr. Cho.' Mr. Lee ordered.

'But Donghae is as soft as a pillow.' Kyu whined.

'Donghae is not a tool for you to use, Mr. Cho.' Mr. Lee barked.

'Sir?' TOP raised his hand.

'Mr. Choi?'

'Why do you call Kyu and I with our surnames and Donghae by his first?' TOP asked.

Kyu smirked at the faint touch of pink appearing on Mr. Lee's cheeks.

'TOP, think about it, Mr. Lee and I have the same surname, it would be so weird!' Donghae said.

'Ahhh, so true.' TOP nodded.

Kyu snorted.

Mr. Lee cleared his throat. 'The goal of today's biology lesson is self defense. Preserve your own life.'

Kyu smiled softly as he realised why Hyuk was doing this.

'Show me your protection.' Mr. Lee ordered.

Hae lifted his shield, Kyu conjured a metal shield and a sword, while TOP just stood there. Hae noticed and quickly protected TOP as well.

'Donghae, no.' Mr. Lee said.

'But sir, his power doesn't allow him to defend.' Hae pouted.

Mr. Lee just kept staring until Hae lowered the shield.

'Some powers allow both defense as offense, others only one of those or none.' Mr. Lee said. 'Mr. Choi, try to push Donghae away.'

TOP created a shockwave and pointed it at Hae, it had no effect.

'Now do the same to Mr. Cho.' Mr. Lee ordered.

'Noooo, wait!' Kyu yelled.

Kyu got blown away and landed in the lake. TOP and Hae were giggling, enjoying a thoroughly pissed off hunter.

'What the hell, Hyuk. That is so not funny!' Kyu yelled as he pulled himself out the lake. Hae stretched out his hand and removed the water drops from Kyu's body, drying him within the second.

'As you can see, some defense measures don't weigh up against certain offensive powers.' Mr. Lee said slyly.

' you, Hyuk!' Kyu cussed.

'Some combinations are dangerous as well.' Mr. Lee continued. 'I think we all can recall the moment when Donghae and Sungmin tried to protect Mr. Cho at the same time.'

Kyu growled.

'So, it's important on the battlefield that we work in sync, protecting each other but above all you must protect yourself.' Mr. Lee stared at Hae. 'Donghae, tell me why it's important to protect oneself.'

Hae looked a bit guilty and became restless. 'If I don't protect myself, I can't protect others anymore either.'

A beautiful loving smile appeared on Mr. Lee's face. Hyuk shortly fell out of his role as he heard the perfect answer from his boyfriend's lips. He walked up to Hae and kissed him gently.

Kyu coughed but couldn't hide a genuine smile as he understood what was going on.

'Eeeeewwww teacher, you can't kiss Donghae!' TOP cried out.

Hyuk pulled back. 'Mr. Choi, use your other power on Ha-Donghae, please.' Mr. Lee said.

TOP closed his eyes and tried to sense any anger within Hae. 'I can't, sir, he has nothing that I can work with.'

'That's another important lesson, be aware of your own thoughts and feelings, they can go against you!' Mr. Lee explained.

'Donghae, use your water darts on that tree over there.' Mr. Lee instructed.

Hae obeyed and slammed a couple of hundred of them in the tree.

'Okay, do it again.' Mr. Lee said.

This time, Mr. Lee lowered the temperature of the water turning the darts in ice, causing way more damage to the tree. 'Sometimes we need to work together, some powers can amplify one another.' Mr. Lee explained. He threw a ray of fire, Hae added water and hot steam was created. TOP was in full admiration. 'You guys are so cool!'

Heechul was staring out the window, he, Siwon and GD were looking at Hyuk's lesson.

'Hyuk is terrified.' Heechul sighed.

'Normal reaction when you learn the entire ing universe is against your lover.' GD said.

Siwon cocked up an eyebrow. 'That's a bit strong. Only Leeteuk is.'

'Like I said, the entire ing universe.' GD repeated.

'Is Onew back yet?' Heechul asked.

'Not that I've seen. Then again, we all know he'll do more than just test if Luna will go against her brother of not.' GD smirked.

'You think we can protect Hae?' Siwon asked.

'I hope so.' Heechul said.

'We better.' GD added as he saw Hyuk kiss Hae.

'I'm going to cancel Physics, since it took you guys too long to learn the other lessons.' Mr. Lee said curtly. 'Get changed into your PE clothes and come back outside.'

The three students quickly ran back inside to change. A couple of minutes the boys returned.

'What are you wearing?' TOP's eyes grew large as he watched Hae in his tight shorts and wifebeater. Mr. Lee started coughing as Kyu sent him a death glare.

'These are my PE clothes.' Hae blinked innocently.

'You and I need a nice, long talk about you ing on my best friend.' Kyu hissed angrily in Hyuk's ear.