I have help from Piper:

Nico POV

It was a little past midnight, but I lay wide awake on the couch, having an internal crisis with myself. Will was asleep next to me, covered in a bundle of blankets. His face was so peaceful and cute, but I tried not to look at it. Every time I did I was reminded that I had feelings, towards a puny mortal!?!

I groaned and got up. I can't believe it. I need to speak to someone about this. I can't take this anymore! I took out a slip of paper from my bag and quickly scribbled out a note.

Dear Will,

I'm so, so , so sorry but I have to go home.
I'm not abandoning you!
I promise I will make it up to you.
I felt very sick, maybe even homesick.
It's not often I get ill, and I don't want you to catch whatever I have.
I promise I will make this up to you, really I'm not kidding! Sorry again.
-Nico xxx

Then it about feeling sick wasn't a lie, but really? Home sick! I'm like the least likely person to ever get homesick. I snuck out of his house quietly. My bag on my back, my sword drawn in case there were any monsters outside.
Once the I made sure the coast was clear, I sprinted silently back to my house. I slipped in through the front door and carefully made my way upstairs.

"Pipers room."

I whispered knocking three times on the wall.

"Permission granted!"
Pipers sing song voice called out as a light blue door appeared in the wall. I took a deep breathe as I turned the door knob and entered the room. Piper herself was sprawled out on her bed, her choppy auburn hair handing down loosely, her newly manicured hand poised above a box of multi coloured feathers she was arranging. Just because piper is a siren, does not mean everything she owns was pink, but a fair share of her room was. Sirens are known for being the go to person for all things to do with love. I just prayed she would help me now.

"Well, well Nico! Didn't expect to see you back so soon. Weren't you supposed to be staying the night at Wills house?"
Piper said inviting me over to sit with her on her bed.I gulped.

"Well you see, Piper... that's kinda the problem."

Piper raised an eyebrow.

"Elaborate please."

Well here I go.

"Piper... I think... I felt it.... I don'tknow what to do! And ..... I don't ... but I ..."
I gave a shaking breath, looked Piper dead in the eye. Then said as firmly as I could.

"I am in love with Will Solace!"

Pipers said nothing for a second. Then let out the loudest squeal known to warlock Kind.

"Piper! Shut up! Your going to wake someone!"

"Sorry Nico! Besides my walls are soundproof."
Piper giggled, swooning and fanning herself.

"Oh Nico! This so perfect! You are in love! Wait- wait- let me check."

Piper leant over to me, way too closed for comfort, and sniffed me. I shoved her away.

"Piper what the heck?!?"

Piper ignored my shove and instead gasped, her eyes shining with excitement.
"Nico! It's true! Pure love! I can smell it! You really are in love."
She elbowed me playfully.
"In love with a mortal !"

I scowled at her. Why did I even bother asking her?

"Thanks for confirming that Piper, it's not like I didn't know that already. Not with that stupid pain in my stomach telling me so!"

"Oh yeah, hang on I have a remedy for that!"
Piper sighed apologetically, and got up to get the potion. She came back with a small vail filled with herbs and neon pink flowers. She placed it into my hand.

"Here! Drink this! It should help with the Warlock love cramps."

I downed the potion, which tasted of chocolate strawberries, as Piper sat back down next to me on her bed.

"What else happened to a warlock when in love? It's been so long I have forgotten!"

Piper looked thoughtful for a second, the as if reading out ingredients for a cake, began listing all the symptoms.

"Well, the love cramps are the most obvious sign, they will go away once you confess! You will feel very protective over Will, you might have random mood swings when that person is present, where you get all emotional and start to spill your life secrets, if your rejected, it will probably hurt a lot!"

I groaned.
"Don't remind me! I already had that happen once!"

Piper bit her lip.
"Percy .."
I scowled at her.
"I said don't remind me Piper!"
She nodded quickly.

I lay back in her bed and gave a long sigh.

"What am I going to do Piper? He is a mortal!"

Piper gave me a disapproving look.

"Nico you can't hate Will for being a mortal!"

I shook my head, my heart heavy.
"It's not that piper! It's just... with the rise of the night happening, most mortals won't make it! And Reyna said those who are already mentally weak will be the first to go! Will has pretty bad anxiety and I already placed a protective charm on him, but I'm worried it won't be enough!"

Realisation dawned on Pipers face as she realised the situation.
"Oh ... oh no."
I sat back up panic rising in my voice.

"If I get rejected I might never love anyone again! And even if I confess and he excepts he is still going to die like all mortals do! I wouldn't be able to handle his death! I love him!"

Pipers face brightened slightly.
"Blessed mortals!"
She whispered.

Not really thinking I turned to her, tears in my eyes.
"What?"

Pipers whole face lit up like a lamp as she yelled excitedly.
"Blessed mortals Nico! The clear sighted mortals- why do you think Annabeth is alive? What is calypso ? Nico this could be the answer!"

Hope suddenly filled my eyes.
"Of course! Percy loved Annabeth back when she was human, and through love turned her into a clear sighted mortal! An immortal mortal! That's brilliant Piper!"
Then my face fell.
"But ... to do that, I need Wills permission, and to have permission he must love me back, and I will have to tell him I'm.. I'm .. I'm a monster!"
Piper gasped and put her hand in my shoulder.

"You are not a monster Nico!"
She said her colour changing eyes staring into mine.
"See if he loves your first, and if he does, then he shouldn't mind the fact your a warlock! Test him!"
I felt frightened.
"But ... what about being rejected?"
Piper bit her crimson red lips avoiding my eye contact.
"It's a risk you will have to take I'm afraid."

I pondered my options. Could I really take another rejection? And what about the possibility of Will hating me after discovering I'm a warlock! But what about Will? He deserves more than the life he has been given! He is so kind and sweet and I love him to much to turn this opportunity down.

"I'll do it!"
I said to piper, barely a whisper but she still heard me.

"Yay Nico!"
She squealed.

"How do I get him to love me?"
I asked nervously.
Piper broke out into the biggest grin I have ever seen.
"I think I have just the idea!"