  We propose a triple-star scenario where the merger of two pre-main sequence
low mass stars, <0.5Mo, ejects a dusty equatorial outflow that obscures and
temporarily causes the disappearance of a massive star, >8Mo. The merger of the
low-mass inner binary powers a faint outburst, i.e., a faint intermediate
luminosity optical transient (ILOT), but its main effect that can last for
decades is to (almost) disappear the luminous massive star of the triple
system. The typical orbital period of the triple system in about a year. The
merger process proceeds as the more massive star of the two low-mass pre-main
sequence star starts to transfer mass to the least massive star in the triple
system and as a result of that expands. This 'type II obscuring ILOT' scenario
in a triple star system might account for the fading, re-brightening, and then
re-fading of the massive post-main sequence star M101-OC1. It might recover in
about 20-100 year. Our study strengthens the claim that there are alternative
scenarios to account for the (almost) disappearing of massive stars, removing
the need for failed supernovae. In these scenarios the disappearing is
temporary, months to decades, and therefore at later time the massive star
explodes as a core collapse supernova even if it forms a black hole.
