https://www.youtube.com/watch?v=4d44kVV-AjY

I would love to share some of the songs Ive been stuck on lately :) And I think most, if not all, have complicated meaning behind them.

Thrice - Black Honey - https://youtu.be/C9GTEsNf_GU - Found these guys just surfing through YT.. Catchy as hell.
Highly Suspects. Two songs from these guys that has been in my playlist for some time. https://youtu.be/l5-gja10qkw and https://youtu.be/ev-bR9ii7Gs
Here maybe something down the aisle your looking at - HELLYEAH - Love Falls. https://youtu.be/iFdOAyyn76M
This ones somewhat about love - https://youtu.be/tIgtaM7OV4g
I think Stone Sour is great addition to this list. https://youtu.be/l-h0QJDCmxo . Other songs too. No need to list them all here. This one as reference and check out their other songs, too. If your not already familiar with them :)
And in conclusion I must mention some of my favorite groups - In This Moment, Pretty Reckless and Halestorm. All these groups have awesome songs with different styles. Check them out ;)

Good Luck.

Black Cat Bones - Please Tell Me Babe ->
Black Cat Bones - Good Looking Woman ->
Blue Oyster Cult - She's As Beautiful As A Foot -> https://www.youtube.com/watch?v=FpCB-0d42-g
Cream - Swlabr -> https://www.youtube.com/watch?v=ngIxuGOVGeQ
Cream - Strange Brew-> https://www.youtube.com/watch?v=m_NholHANoY
Cream - Sunshine Of Your Love -> https://www.youtube.com/watch?v=zt51rITH3EA
Electric Six - Danger! High Voltage -.
Gov't Mule - Beautifully Broken ->
Heart - Crazy On You -> https://www.youtube.com/watch?v=OZuW6BH_Vak
Heart - I Want you So Bad ->
Heart - All I Wanna Do Is Make Love To You ->
Heart - I Didn't Want To Need You ->
Iron Butterfly - It Must Be Love ->
Jericho - Kill Me With Your Love ->
Quick Silver Message - Who Do You Love (Part 1) ->
Ten Year After - Love Until I Die ->
The Animals - Hallelujah I Love Her So ->
The Animals - Let the Good Times Roll ->
The Animals - Baby Let Me Take You Home ->
The Beatles - I Want You (She's So Heavy) ->
Tin House - I Want Your Body ->
Toad - I Saw Her Standing There ->
UFO - Only You Can Rock Me ->
UFO - Love To Love ->

etc so much stuff out there, got to lazy to adding the youtube links :P

'#'1 Romantic rock song ;)

Airbourne - Diamond In The Rough ->

I could give a troll answer and recommend
Rammstein - Heirate Mich. Which sounds romantic because it translates to "Marry me". The lyrics deal with misguided necrophilia though

A more legit and light-hearted answer.
Spin Doctors - Two Princes

Wow. What has the world come to when you go on a forum to ask for music to flirt with a girl? You should grow a better music catalog that reflects yourself more. That being said, I'll give you these songs, since I'm a good person at heart;
White Lies - Strangers - Unfinished Business - Bigger Than Us - E.S.T.
Arctic Monkeys - Do I Wanna Know? - R U Mine? - I Wanna Be Yours - From The Ritz To The Rubble
Placebo - Running Up That Hill - Life's What You Make It - Every You Every Me - Infra Red
U2 - Acrobat - Ultra Violet - Until The End Of The World
VAST - Touched
New Order - Crystal
Good luck.

Back to the Future (short videos)
https://www.youtube.com/watch?v=3isQI0nXQRE
https://www.youtube.com/watch?v=o6ge6x0EHQA
https://www.youtube.com/watch?v=WNtmITE5GpU
https://www.youtube.com/watch?v=S1i5coU-0_Q