He doesn't have Twitter.
Profile pictures on Twitter are usually refered to as 'icons', although there is no official name for them.
This is the location the tweet was posted from.
@Jay_Tommo_
@Louis_Tomlinson
Your name is displayed on your profile but you aren't required to use your real name.
Louis_Tomlinson
@JohannahDarling
@JohannahDarling
Louis' mums name is Johannah (Jay) Tomlinson.
name: @Louis_Tomlinson password: imsexyandiknowit
The ability to change your username is not currently supported on Twitter's mobile apps.To change your Twitter profile name on your laptop:Log inClick on your avatar in the upper right hand corner of your screen, and on the drop-down menu, choose "Settings."Choose the "Account" tab on the left.In the "Username" field, type in your new username.Click "Save Changes" at the bottom.
Harry; Hazza_(your first name) Liam; PayneForLiam Zayn; VasHappenin(number) Louis; Louis-(your name) Niall; irishIhadChicken