surreptitiously russian

• тайко́м

  secretly, in secret, on the sly, surreptitiously

  behind somebody's back, without somebody's knowledge

• подки́дывающий

  tossing, throwing up, flinging up

  planting (surreptitiously), slipping in, covertly placing

• подсо́вывавший

  who was slipping in, who was foisting, who was surreptitiously placing