Having sensationally knocked out Barcelona in the last round thanks to a 3-0 home win, the Italian club know the same result again on Wednesday will see them progress to the final.
Liverpool will travel to the Stadio Olimpico as favourites, however, after Jurgen Klopp's side recorded a 5-2 victory in the first leg.
The game at Anfield was marred by issues outside the ground prior to kick-off, with two Italian men charged and remanded in custody by Merseyside Police after an incident in which a 53-year-old was seriously injured.
While Monchi wants all home fans to show their support as they bid to pull off another famous European comeback, he also revealed his hope for the fixture to pass without any issues.
"I'd like Rome to be decked out in yellow and red, and for all the fans to hang banners on their balconies to show the world that Rome supports Roma," Monchi said in an interview with Il Romanista.
"There's a lot of talk about violence right now, so let’s show everyone that Roma fans are not violent."
Roma trailed 5-0 on Merseyside after 68 minutes but have a glimmer of hope in the tie thanks to late goals from Edin Dzeko and Diego Perotti.
Monchi appreciates they face a tall order to turn around the deficit against the leading scorers in this season's Champions League, though the Serie A side have kept five successive clean sheets at home in the competition.
"It is the time to be united. Beating Liverpool will be harder than beating Barcelona. There is no tomorrow, everything finishes on Wednesday, and we must make sure we leave everything out on the pitch," Sevilla's former director of football said.
"Every grandfather, grandson, father, mother: on Wednesday we are playing for everyone.
"I was lucky enough to win a lot at Sevilla, but I never realised my dream of reaching the Champions League final.
"Everyone needs to do what they have to do. Alisson makes a save, Dzeko scores a goal, Daniele [De Rossi] with a pass, the other guys not playing showing their full support for the guys on the pitch.
"And we have to be absolutely convinced we can do it, because then it is easy to go out and do it."