Harry has a symbol for 'Equal Love' on his arm.
Harry has a boat tattoo, Louis has a compass tattoo.
Harry has a padlock tattoo, and Louis has a key tattoo.
Harry has "hi" written in Louis' handwriting, Louis has an "oops" tattoo in Harry's handwriting.
Harry has a bird cage tattoo, Louis has bird tattoos.
Harry has a tattoo that says 'I can't change', and Louis has quotation marks.