Close friends have revealed they are anxious because they "cannot get hold of him", since leaving the villa.
Another of Niall's mates added: "We just found out when it came on the press". He described himself as a "rainbow fish" and said his best attribute was his "chat" - although the girls on Love Island seemed to be just as taken with his looks.
Love Island sources told The Mirror that a recoupling is "imminent" as Niall's departure means the couples will have to switch up their partners sooner then they originally planned.
"He is really popular as he's a lovely boy".
In Tuesday's episode Alex announces: "For personal reasons unfortunately he [Niall] can't continue or come back to the villa".
Love Island: Female contestants from past three series of Caroline Flack's ITV2 show.
Obviously I was coupled up with him so obviously I came closer to him than most people in here but it wasn't just that.
Alex was also sad about Niall's departure. 'He's such a great guy. 'We got on really, really well.
'And I look forward to catching up with him and having some fun with him outside'.
Note there's a specific account dedicated to the mystery of why Niall left, that's dedication for you.
Now that the 23-year-old construction worker has left the villa it is unknown who Georgia will couple up with.
'Love Island' airs tonight at 9pm on ITV2.