A fight for love ~ Nagisa X Kayano/Karma (COMPLETED)

The meeting

When Kayano received Nagisa's reply, her heart fluttered.  Yes!  Yes!  She could come!  She couldn't believe what she was reading!  And... Nagisa hadn't forgotten her.  She felt like a huge weight had been lifted from her shoulders.  After all this time, he had remembered her!!  That night, she fell into dreams of anxiety and relief, but none were as happy as one...

She dreamt that she had married Nagisa.  She dreamt that they lived together.  She dreamt that...
They had a child. 
The child's name was Nami, meaning wave (similarly to Nagisa, meaning seashore). She had purple hair, which she kept loose, and bright red eyes, which sparkled in the sunlight like she had rubies in her eye-sockets.  Once Kayano woke up, she was disappointed to see that it was a dream...

The next day, she rushed to the address that Nagisa gave her, and got there 5 minutes early!  Nagisa arrived early as well, so he greeted her at the door, and- blushing- she stepped inside...  A few early students were waiting in the playground, and greeted Nagisa with a friendly grin.
"Hi Hoshiko! Hi Chikako! Hi Namiko!" He called.
"Hi sir! Who's this?" Asked Namiko.
"Oh, this is Kaede Kayano, my childhood friend!" Replied Nagisa.
"Wha- oh, hi!" Kayano was flustered because she was just looking around and thinking about Nagisa and Nami.
"Ooooh is she that childhood friend, sir?" Asked Hoshiko.
"Erm... Well, yes, but-"
Hoshiko and Chikako exchanged evil grins, and Kayano just looked confused.
"What do you-"
"Welp! I think we need to go inside and get ready now, bye guys!"
"Bye sir!"

Once they got inside, Nagisa gave Kayano some homemade dango that he had put together, and for dessert they had-
"PUDDING!" Screamed Kayano, as Nagisa pulled a huge pudding out of the oven.  "Yeah, I told my class that you were coming, so Chikako made this pudding as a gift for you!" Nagisa remembered her exact words...
"You have to share it, okay?"
"Do you want to share? It was your pupil who made it after all!" Laughed Kayano.
"Oh, sure! She actually told me that we should share, for some reason!" Replied Nagisa.  "Oh, wait I forgot to get a spoon!"
"You're still as forgetful as ever then!"
After a few minutes of laughing and chatting about old times, a bullet flew past them, just skimming Nagisa's ear.  "Wha- what's going on!!!" Yelled Kayano, rattled by the bullet's sudden appearance, but Nagisa, to Kayano's surprise, just laughed!  "Alright Hiromasa!  You can come out now!"
"Aww, sir, how did you know it was me?"
"I saw a tuft of your hair; I would recognise that ginger hair anywhere!" Nagisa smiled.  "But no assassination attempts before class starts, you know that!"
"Sorry sir!" Said Hiromasa, sheepishly.  Assassination attempts.  So, was this...

An assassination classroom..?