When we see them? Yes, indeed.
Have I ever seen one? Not that I know of, but I would not state with certainty that I have not seen an angel - be it a fallen angel or one of God's own angelic host. And I think I would know since they don't usually wander around with a lack of purpose when they visit.
I am certain, though, that they have been involved in my life on many occasions, since assisting and protecting God's people is the primary concern of a portion of the angelic hierarchy who are assigned to that task. And of course the fallen angels have their agendas, too (and I'm pretty sure I was on that list).
I fully expect to be seeing them as our encounters in the spiritual battle intensify and ultimately lead to living on earth with Jesus Christ himself, who will reign and rule here in the very near future. I fully expect to see Him and the angelic host.
I'm afraid most people are so preoccupied with living 'in the flesh,' so out of tune with spiritual realities, that they envision angels as Caspar the friendly ghost wafting around. That's not it.
There are also increasing numbers of people who are involved in such strictly forbidden activities as transcendental meditation and that whole New Age scene (even many who claim to be Christian), and are meeting up with entities. They believe these personages to be spirit guides or representations of God, when in reality they are encountering demonic entities.
These people are seeking an experience; it's what they feel that counts. They fall for every phony TV preacher who tells about his 'experience' when he went to heaven. We are explicitly warned against all this.
"Unless you people see signs and wonders, you simply will not believe." John 4:48
"Beloved, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world." 1 John 4:1
Testing the spirits involves lining things up with scripture, which is always the final authority. In approximately ten out of ten cases, I have found that the stories told by these people are as transparently false as can be - not the experience itself, but the legitimacy of it.
With a very few exceptions in biblical history, God does not work this way. We are to live by faith.
"...and though you have not seen Him, you love Him, and though you do not see Him now, but believe in Him, you greatly rejoice with joy inexpressible and full of glory." 1 Peter 1:8
'Jesus said to him, "Because you have seen Me, have you believed? Blessed are they who did not see, and yet believed."' John 20:29
I was headed in a completely different direction with this post when I wrote the first two short paragraphs above, but was led off in a different direction. Lest I leave you hanging with the opening teaser, let me assure you that I will be writing more about these angel persons as we go along. It is one of my favorite areas of study and an area in which it is critical that we be educated in these last days because most people are totally and dangerously misinformed about angels and demons.